/** * Copyright 2014 Netflix, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in * compliance with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software distributed under the License is * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See * the License for the specific language governing permissions and limitations under the License. */ package rx; import java.util.*; import java.util.concurrent.*; import rx.annotations.*; import rx.exceptions.*; import rx.functions.*; import rx.internal.operators.*; import rx.internal.util.*; import rx.observables.*; import rx.observers.SafeSubscriber; import rx.plugins.*; import rx.schedulers.*; import rx.subjects.*; import rx.subscriptions.Subscriptions; /** * The Observable class that implements the Reactive Pattern. * <p> * This class provides methods for subscribing to the Observable as well as delegate methods to the various * Observers. * <p> * The documentation for this class makes use of marble diagrams. The following legend explains these diagrams: * <p> * <img width="640" height="301" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/legend.png" alt=""> * <p> * For more information see the <a href="http://reactivex.io/documentation/observable.html">ReactiveX * documentation</a>. * * @param <T> * the type of the items emitted by the Observable */ public class Observable<T> { final OnSubscribe<T> onSubscribe; /** * Creates an Observable with a Function to execute when it is subscribed to. * <p> * <em>Note:</em> Use {@link #create(OnSubscribe)} to create an Observable, instead of this constructor, * unless you specifically have a need for inheritance. * * @param f * {@link OnSubscribe} to be executed when {@link #subscribe(Subscriber)} is called */ protected Observable(OnSubscribe<T> f) { this.onSubscribe = f; } private static final RxJavaObservableExecutionHook hook = RxJavaPlugins.getInstance().getObservableExecutionHook(); /** * Returns an Observable that will execute the specified function when a {@link Subscriber} subscribes to * it. * <p> * <img width="640" height="200" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/create.png" alt=""> * <p> * Write the function you pass to {@code create} so that it behaves as an Observable: It should invoke the * Subscriber's {@link Subscriber#onNext onNext}, {@link Subscriber#onError onError}, and * {@link Subscriber#onCompleted onCompleted} methods appropriately. * <p> * A well-formed Observable must invoke either the Subscriber's {@code onCompleted} method exactly once or * its {@code onError} method exactly once. * <p> * See <a href="http://go.microsoft.com/fwlink/?LinkID=205219">Rx Design Guidelines (PDF)</a> for detailed * information. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code create} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <T> * the type of the items that this Observable emits * @param f * a function that accepts an {@code Subscriber<T>}, and invokes its {@code onNext}, * {@code onError}, and {@code onCompleted} methods as appropriate * @return an Observable that, when a {@link Subscriber} subscribes to it, will execute the specified * function * @see <a href="http://reactivex.io/documentation/operators/create.html">ReactiveX operators documentation: Create</a> */ public final static <T> Observable<T> create(OnSubscribe<T> f) { return new Observable<T>(hook.onCreate(f)); } /** * Invoked when Observable.subscribe is called. */ public interface OnSubscribe<T> extends Action1<Subscriber<? super T>> { // cover for generics insanity } /** * Operator function for lifting into an Observable. */ public interface Operator<R, T> extends Func1<Subscriber<? super R>, Subscriber<? super T>> { // cover for generics insanity } /** * Lifts a function to the current Observable and returns a new Observable that when subscribed to will pass * the values of the current Observable through the Operator function. * <p> * In other words, this allows chaining Observers together on an Observable for acting on the values within * the Observable. * <p> {@code * observable.map(...).filter(...).take(5).lift(new OperatorA()).lift(new OperatorB(...)).subscribe() * } * <p> * If the operator you are creating is designed to act on the individual items emitted by a source * Observable, use {@code lift}. If your operator is designed to transform the source Observable as a whole * (for instance, by applying a particular set of existing RxJava operators to it) use {@link #compose}. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code lift} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param lift the Operator that implements the Observable-operating function to be applied to the source * Observable * @return an Observable that is the result of applying the lifted Operator to the source Observable * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Implementing-Your-Own-Operators">RxJava wiki: Implementing Your Own Operators</a> */ public final <R> Observable<R> lift(final Operator<? extends R, ? super T> lift) { return new Observable<R>(new OnSubscribe<R>() { @Override public void call(Subscriber<? super R> o) { try { Subscriber<? super T> st = hook.onLift(lift).call(o); try { // new Subscriber created and being subscribed with so 'onStart' it st.onStart(); onSubscribe.call(st); } catch (Throwable e) { // localized capture of errors rather than it skipping all operators // and ending up in the try/catch of the subscribe method which then // prevents onErrorResumeNext and other similar approaches to error handling if (e instanceof OnErrorNotImplementedException) { throw (OnErrorNotImplementedException) e; } st.onError(e); } } catch (Throwable e) { if (e instanceof OnErrorNotImplementedException) { throw (OnErrorNotImplementedException) e; } // if the lift function failed all we can do is pass the error to the final Subscriber // as we don't have the operator available to us o.onError(e); } } }); } /** * Transform an Observable by applying a particular Transformer function to it. * <p> * This method operates on the Observable itself whereas {@link #lift} operates on the Observable's * Subscribers or Observers. * <p> * If the operator you are creating is designed to act on the individual items emitted by a source * Observable, use {@link #lift}. If your operator is designed to transform the source Observable as a whole * (for instance, by applying a particular set of existing RxJava operators to it) use {@code compose}. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code compose} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param transformer implements the function that transforms the source Observable * @return the source Observable, transformed by the transformer function * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Implementing-Your-Own-Operators">RxJava wiki: Implementing Your Own Operators</a> */ @SuppressWarnings("unchecked") public <R> Observable<R> compose(Transformer<? super T, ? extends R> transformer) { return ((Transformer<T, R>) transformer).call(this); } /** * Transformer function used by {@link #compose}. * @warn more complete description needed */ public interface Transformer<T, R> extends Func1<Observable<T>, Observable<R>> { // cover for generics insanity } /* ********************************************************************************************************* * Operators Below Here * ********************************************************************************************************* */ /** * Mirrors the one Observable in an Iterable of several Observables that first either emits an item or sends * a termination notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param sources * an Iterable of Observable sources competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Iterable<? extends Observable<? extends T>> sources) { return create(OnSubscribeAmb.amb(sources)); } /** * Given two Observables, mirrors the one that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * an Observable competing to react first * @param o2 * an Observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2) { return create(OnSubscribeAmb.amb(o1, o2)); } /** * Given three Observables, mirrors the one that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * an Observable competing to react first * @param o2 * an Observable competing to react first * @param o3 * an Observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3) { return create(OnSubscribeAmb.amb(o1, o2, o3)); } /** * Given four Observables, mirrors the one that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * an Observable competing to react first * @param o2 * an Observable competing to react first * @param o3 * an Observable competing to react first * @param o4 * an Observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4) { return create(OnSubscribeAmb.amb(o1, o2, o3, o4)); } /** * Given five Observables, mirrors the one that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * an Observable competing to react first * @param o2 * an Observable competing to react first * @param o3 * an Observable competing to react first * @param o4 * an Observable competing to react first * @param o5 * an Observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5) { return create(OnSubscribeAmb.amb(o1, o2, o3, o4, o5)); } /** * Given six Observables, mirrors the one that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * an Observable competing to react first * @param o2 * an Observable competing to react first * @param o3 * an Observable competing to react first * @param o4 * an Observable competing to react first * @param o5 * an Observable competing to react first * @param o6 * an Observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5, Observable<? extends T> o6) { return create(OnSubscribeAmb.amb(o1, o2, o3, o4, o5, o6)); } /** * Given seven Observables, mirrors the one that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * an Observable competing to react first * @param o2 * an Observable competing to react first * @param o3 * an Observable competing to react first * @param o4 * an Observable competing to react first * @param o5 * an Observable competing to react first * @param o6 * an Observable competing to react first * @param o7 * an Observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5, Observable<? extends T> o6, Observable<? extends T> o7) { return create(OnSubscribeAmb.amb(o1, o2, o3, o4, o5, o6, o7)); } /** * Given eight Observables, mirrors the one that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * an Observable competing to react first * @param o2 * an Observable competing to react first * @param o3 * an Observable competing to react first * @param o4 * an Observable competing to react first * @param o5 * an Observable competing to react first * @param o6 * an Observable competing to react first * @param o7 * an Observable competing to react first * @param o8 * an observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5, Observable<? extends T> o6, Observable<? extends T> o7, Observable<? extends T> o8) { return create(OnSubscribeAmb.amb(o1, o2, o3, o4, o5, o6, o7, o8)); } /** * Given nine Observables, mirrors the one that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * an Observable competing to react first * @param o2 * an Observable competing to react first * @param o3 * an Observable competing to react first * @param o4 * an Observable competing to react first * @param o5 * an Observable competing to react first * @param o6 * an Observable competing to react first * @param o7 * an Observable competing to react first * @param o8 * an Observable competing to react first * @param o9 * an Observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final static <T> Observable<T> amb(Observable<? extends T> o1, Observable<? extends T> o2, Observable<? extends T> o3, Observable<? extends T> o4, Observable<? extends T> o5, Observable<? extends T> o6, Observable<? extends T> o7, Observable<? extends T> o8, Observable<? extends T> o9) { return create(OnSubscribeAmb.amb(o1, o2, o3, o4, o5, o6, o7, o8, o9)); } /** * Combines two source Observables by emitting an item that aggregates the latest values of each of the * source Observables each time an item is received from either of the source Observables, where this * aggregation is defined by a specified function. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/combineLatest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * the second source Observable * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @SuppressWarnings("unchecked") public static final <T1, T2, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Func2<? super T1, ? super T2, ? extends R> combineFunction) { return combineLatest(Arrays.asList(o1, o2), Functions.fromFunc(combineFunction)); } /** * Combines three source Observables by emitting an item that aggregates the latest values of each of the * source Observables each time an item is received from any of the source Observables, where this * aggregation is defined by a specified function. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/combineLatest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * the second source Observable * @param o3 * the third source Observable * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @SuppressWarnings("unchecked") public static final <T1, T2, T3, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Func3<? super T1, ? super T2, ? super T3, ? extends R> combineFunction) { return combineLatest(Arrays.asList(o1, o2, o3), Functions.fromFunc(combineFunction)); } /** * Combines four source Observables by emitting an item that aggregates the latest values of each of the * source Observables each time an item is received from any of the source Observables, where this * aggregation is defined by a specified function. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/combineLatest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * the second source Observable * @param o3 * the third source Observable * @param o4 * the fourth source Observable * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @SuppressWarnings("unchecked") public static final <T1, T2, T3, T4, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Func4<? super T1, ? super T2, ? super T3, ? super T4, ? extends R> combineFunction) { return combineLatest(Arrays.asList(o1, o2, o3, o4), Functions.fromFunc(combineFunction)); } /** * Combines five source Observables by emitting an item that aggregates the latest values of each of the * source Observables each time an item is received from any of the source Observables, where this * aggregation is defined by a specified function. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/combineLatest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * the second source Observable * @param o3 * the third source Observable * @param o4 * the fourth source Observable * @param o5 * the fifth source Observable * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @SuppressWarnings("unchecked") public static final <T1, T2, T3, T4, T5, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Func5<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? extends R> combineFunction) { return combineLatest(Arrays.asList(o1, o2, o3, o4, o5), Functions.fromFunc(combineFunction)); } /** * Combines six source Observables by emitting an item that aggregates the latest values of each of the * source Observables each time an item is received from any of the source Observables, where this * aggregation is defined by a specified function. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/combineLatest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * the second source Observable * @param o3 * the third source Observable * @param o4 * the fourth source Observable * @param o5 * the fifth source Observable * @param o6 * the sixth source Observable * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @SuppressWarnings("unchecked") public static final <T1, T2, T3, T4, T5, T6, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Func6<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? extends R> combineFunction) { return combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6), Functions.fromFunc(combineFunction)); } /** * Combines seven source Observables by emitting an item that aggregates the latest values of each of the * source Observables each time an item is received from any of the source Observables, where this * aggregation is defined by a specified function. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/combineLatest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * the second source Observable * @param o3 * the third source Observable * @param o4 * the fourth source Observable * @param o5 * the fifth source Observable * @param o6 * the sixth source Observable * @param o7 * the seventh source Observable * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @SuppressWarnings("unchecked") public static final <T1, T2, T3, T4, T5, T6, T7, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7, Func7<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? extends R> combineFunction) { return combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7), Functions.fromFunc(combineFunction)); } /** * Combines eight source Observables by emitting an item that aggregates the latest values of each of the * source Observables each time an item is received from any of the source Observables, where this * aggregation is defined by a specified function. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/combineLatest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * the second source Observable * @param o3 * the third source Observable * @param o4 * the fourth source Observable * @param o5 * the fifth source Observable * @param o6 * the sixth source Observable * @param o7 * the seventh source Observable * @param o8 * the eighth source Observable * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @SuppressWarnings("unchecked") public static final <T1, T2, T3, T4, T5, T6, T7, T8, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7, Observable<? extends T8> o8, Func8<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? super T8, ? extends R> combineFunction) { return combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7, o8), Functions.fromFunc(combineFunction)); } /** * Combines nine source Observables by emitting an item that aggregates the latest values of each of the * source Observables each time an item is received from any of the source Observables, where this * aggregation is defined by a specified function. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/combineLatest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * the second source Observable * @param o3 * the third source Observable * @param o4 * the fourth source Observable * @param o5 * the fifth source Observable * @param o6 * the sixth source Observable * @param o7 * the seventh source Observable * @param o8 * the eighth source Observable * @param o9 * the ninth source Observable * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @SuppressWarnings("unchecked") public static final <T1, T2, T3, T4, T5, T6, T7, T8, T9, R> Observable<R> combineLatest(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7, Observable<? extends T8> o8, Observable<? extends T9> o9, Func9<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? super T8, ? super T9, ? extends R> combineFunction) { return combineLatest(Arrays.asList(o1, o2, o3, o4, o5, o6, o7, o8, o9), Functions.fromFunc(combineFunction)); } /** * Combines a list of source Observables by emitting an item that aggregates the latest values of each of * the source Observables each time an item is received from any of the source Observables, where this * aggregation is defined by a specified function. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code combineLatest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <T> * the common base type of source values * @param <R> * the result type * @param sources * the list of source Observables * @param combineFunction * the aggregation function used to combine the items emitted by the source Observables * @return an Observable that emits items that are the result of combining the items emitted by the source * Observables by means of the given aggregation function * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ public static final <T, R> Observable<R> combineLatest(List<? extends Observable<? extends T>> sources, FuncN<? extends R> combineFunction) { return create(new OnSubscribeCombineLatest<T, R>(sources, combineFunction)); } /** * Returns an Observable that emits the items emitted by each of the Observables emitted by the source * Observable, one after the other, without interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param observables * an Observable that emits Observables * @return an Observable that emits items all of the items emitted by the Observables emitted by * {@code observables}, one after the other, without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends Observable<? extends T>> observables) { return observables.lift(OperatorConcat.<T>instance()); } /** * Returns an Observable that emits the items emitted by two Observables, one after the other, without * interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated * @param t2 * an Observable to be concatenated * @return an Observable that emits items emitted by the two source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends T> t1, Observable<? extends T> t2) { return concat(just(t1, t2)); } /** * Returns an Observable that emits the items emitted by three Observables, one after the other, without * interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated * @param t2 * an Observable to be concatenated * @param t3 * an Observable to be concatenated * @return an Observable that emits items emitted by the three source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3) { return concat(just(t1, t2, t3)); } /** * Returns an Observable that emits the items emitted by four Observables, one after the other, without * interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated * @param t2 * an Observable to be concatenated * @param t3 * an Observable to be concatenated * @param t4 * an Observable to be concatenated * @return an Observable that emits items emitted by the four source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4) { return concat(just(t1, t2, t3, t4)); } /** * Returns an Observable that emits the items emitted by five Observables, one after the other, without * interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated * @param t2 * an Observable to be concatenated * @param t3 * an Observable to be concatenated * @param t4 * an Observable to be concatenated * @param t5 * an Observable to be concatenated * @return an Observable that emits items emitted by the five source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5) { return concat(just(t1, t2, t3, t4, t5)); } /** * Returns an Observable that emits the items emitted by six Observables, one after the other, without * interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated * @param t2 * an Observable to be concatenated * @param t3 * an Observable to be concatenated * @param t4 * an Observable to be concatenated * @param t5 * an Observable to be concatenated * @param t6 * an Observable to be concatenated * @return an Observable that emits items emitted by the six source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6) { return concat(just(t1, t2, t3, t4, t5, t6)); } /** * Returns an Observable that emits the items emitted by seven Observables, one after the other, without * interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated * @param t2 * an Observable to be concatenated * @param t3 * an Observable to be concatenated * @param t4 * an Observable to be concatenated * @param t5 * an Observable to be concatenated * @param t6 * an Observable to be concatenated * @param t7 * an Observable to be concatenated * @return an Observable that emits items emitted by the seven source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7) { return concat(just(t1, t2, t3, t4, t5, t6, t7)); } /** * Returns an Observable that emits the items emitted by eight Observables, one after the other, without * interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated * @param t2 * an Observable to be concatenated * @param t3 * an Observable to be concatenated * @param t4 * an Observable to be concatenated * @param t5 * an Observable to be concatenated * @param t6 * an Observable to be concatenated * @param t7 * an Observable to be concatenated * @param t8 * an Observable to be concatenated * @return an Observable that emits items emitted by the eight source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7, Observable<? extends T> t8) { return concat(just(t1, t2, t3, t4, t5, t6, t7, t8)); } /** * Returns an Observable that emits the items emitted by nine Observables, one after the other, without * interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated * @param t2 * an Observable to be concatenated * @param t3 * an Observable to be concatenated * @param t4 * an Observable to be concatenated * @param t5 * an Observable to be concatenated * @param t6 * an Observable to be concatenated * @param t7 * an Observable to be concatenated * @param t8 * an Observable to be concatenated * @param t9 * an Observable to be concatenated * @return an Observable that emits items emitted by the nine source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final static <T> Observable<T> concat(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7, Observable<? extends T> t8, Observable<? extends T> t9) { return concat(just(t1, t2, t3, t4, t5, t6, t7, t8, t9)); } /** * Returns an Observable that calls an Observable factory to create an Observable for each new Observer * that subscribes. That is, for each subscriber, the actual Observable that subscriber observes is * determined by the factory function. * <p> * <img width="640" height="340" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/defer.png" alt=""> * <p> * The defer Observer allows you to defer or delay emitting items from an Observable until such time as an * Observer subscribes to the Observable. This allows an {@link Observer} to easily obtain updates or a * refreshed version of the sequence. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code defer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param observableFactory * the Observable factory function to invoke for each {@link Observer} that subscribes to the * resulting Observable * @param <T> * the type of the items emitted by the Observable * @return an Observable whose {@link Observer}s' subscriptions trigger an invocation of the given * Observable factory function * @see <a href="http://reactivex.io/documentation/operators/defer.html">ReactiveX operators documentation: Defer</a> */ public final static <T> Observable<T> defer(Func0<Observable<T>> observableFactory) { return create(new OnSubscribeDefer<T>(observableFactory)); } /** An empty observable which just emits onCompleted to any subscriber. */ private static final Observable<Object> EMPTY = create(new OnSubscribe<Object>() { @Override public void call(Subscriber<? super Object> t1) { t1.onCompleted(); } }); /** * Returns an Observable that emits no items to the {@link Observer} and immediately invokes its * {@link Observer#onCompleted onCompleted} method. * <p> * <img width="640" height="190" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/empty.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code empty} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <T> * the type of the items (ostensibly) emitted by the Observable * @return an Observable that emits no items to the {@link Observer} but immediately invokes the * {@link Observer}'s {@link Observer#onCompleted() onCompleted} method * @see <a href="http://reactivex.io/documentation/operators/empty-never-throw.html">ReactiveX operators documentation: Empty</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> empty() { return (Observable<T>)EMPTY; } /** * Returns an Observable that invokes an {@link Observer}'s {@link Observer#onError onError} method when the * Observer subscribes to it. * <p> * <img width="640" height="190" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/error.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code error} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param exception * the particular Throwable to pass to {@link Observer#onError onError} * @param <T> * the type of the items (ostensibly) emitted by the Observable * @return an Observable that invokes the {@link Observer}'s {@link Observer#onError onError} method when * the Observer subscribes to it * @see <a href="http://reactivex.io/documentation/operators/empty-never-throw.html">ReactiveX operators documentation: Throw</a> */ public final static <T> Observable<T> error(Throwable exception) { return new ThrowObservable<T>(exception); } /** * Converts a {@link Future} into an Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/from.Future.png" alt=""> * <p> * You can convert any object that supports the {@link Future} interface into an Observable that emits the * return value of the {@link Future#get} method of that object, by passing the object into the {@code from} * method. * <p> * <em>Important note:</em> This Observable is blocking; you cannot unsubscribe from it. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code from} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param future * the source {@link Future} * @param <T> * the type of object that the {@link Future} returns, and also the type of item to be emitted by * the resulting Observable * @return an Observable that emits the item from the source {@link Future} * @see <a href="http://reactivex.io/documentation/operators/from.html">ReactiveX operators documentation: From</a> */ public final static <T> Observable<T> from(Future<? extends T> future) { return create(OnSubscribeToObservableFuture.toObservableFuture(future)); } /** * Converts a {@link Future} into an Observable, with a timeout on the Future. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/from.Future.png" alt=""> * <p> * You can convert any object that supports the {@link Future} interface into an Observable that emits the * return value of the {@link Future#get} method of that object, by passing the object into the {@code from} * method. * <p> * <em>Important note:</em> This Observable is blocking; you cannot unsubscribe from it. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code from} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param future * the source {@link Future} * @param timeout * the maximum time to wait before calling {@code get} * @param unit * the {@link TimeUnit} of the {@code timeout} argument * @param <T> * the type of object that the {@link Future} returns, and also the type of item to be emitted by * the resulting Observable * @return an Observable that emits the item from the source {@link Future} * @see <a href="http://reactivex.io/documentation/operators/from.html">ReactiveX operators documentation: From</a> */ public final static <T> Observable<T> from(Future<? extends T> future, long timeout, TimeUnit unit) { return create(OnSubscribeToObservableFuture.toObservableFuture(future, timeout, unit)); } /** * Converts a {@link Future}, operating on a specified {@link Scheduler}, into an Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/from.Future.s.png" alt=""> * <p> * You can convert any object that supports the {@link Future} interface into an Observable that emits the * return value of the {@link Future#get} method of that object, by passing the object into the {@code from} * method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param future * the source {@link Future} * @param scheduler * the {@link Scheduler} to wait for the Future on. Use a Scheduler such as * {@link Schedulers#io()} that can block and wait on the Future * @param <T> * the type of object that the {@link Future} returns, and also the type of item to be emitted by * the resulting Observable * @return an Observable that emits the item from the source {@link Future} * @see <a href="http://reactivex.io/documentation/operators/from.html">ReactiveX operators documentation: From</a> */ public final static <T> Observable<T> from(Future<? extends T> future, Scheduler scheduler) { // TODO in a future revision the Scheduler will become important because we'll start polling instead of blocking on the Future return create(OnSubscribeToObservableFuture.toObservableFuture(future)).subscribeOn(scheduler); } /** * Converts an {@link Iterable} sequence into an Observable that emits the items in the sequence. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/from.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code from} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param iterable * the source {@link Iterable} sequence * @param <T> * the type of items in the {@link Iterable} sequence and the type of items to be emitted by the * resulting Observable * @return an Observable that emits each item in the source {@link Iterable} sequence * @see <a href="http://reactivex.io/documentation/operators/from.html">ReactiveX operators documentation: From</a> */ public final static <T> Observable<T> from(Iterable<? extends T> iterable) { return create(new OnSubscribeFromIterable<T>(iterable)); } /** * Converts an Array into an Observable that emits the items in the Array. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/from.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code from} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param array * the source Array * @param <T> * the type of items in the Array and the type of items to be emitted by the resulting Observable * @return an Observable that emits each item in the source Array * @see <a href="http://reactivex.io/documentation/operators/from.html">ReactiveX operators documentation: From</a> */ public final static <T> Observable<T> from(T[] array) { return from(Arrays.asList(array)); } /** * Returns an Observable that emits a sequential number every specified interval of time. * <p> * <img width="640" height="195" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/interval.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code interval} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param interval * interval size in time units (see below) * @param unit * time units to use for the interval size * @return an Observable that emits a sequential number each time interval * @see <a href="http://reactivex.io/documentation/operators/interval.html">ReactiveX operators documentation: Interval</a> */ public final static Observable<Long> interval(long interval, TimeUnit unit) { return interval(interval, unit, Schedulers.computation()); } /** * Returns an Observable that emits a sequential number every specified interval of time, on a * specified Scheduler. * <p> * <img width="640" height="200" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/interval.s.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param interval * interval size in time units (see below) * @param unit * time units to use for the interval size * @param scheduler * the Scheduler to use for scheduling the items * @return an Observable that emits a sequential number each time interval * @see <a href="http://reactivex.io/documentation/operators/interval.html">ReactiveX operators documentation: Interval</a> */ public final static Observable<Long> interval(long interval, TimeUnit unit, Scheduler scheduler) { return create(new OnSubscribeTimerPeriodically(interval, interval, unit, scheduler)); } /** * Returns an Observable that emits a single item and then completes. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.png" alt=""> * <p> * To convert any object into an Observable that emits that object, pass that object into the {@code just} * method. * <p> * This is similar to the {@link #from(java.lang.Object[])} method, except that {@code from} will convert * an {@link Iterable} object into an Observable that emits each of the items in the Iterable, one at a * time, while the {@code just} method converts an Iterable into an Observable that emits the entire * Iterable as a single item. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param value * the item to emit * @param <T> * the type of that item * @return an Observable that emits {@code value} as a single item and then completes * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ public final static <T> Observable<T> just(final T value) { return ScalarSynchronousObservable.create(value); } /** * Converts two items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2) { return from(Arrays.asList(t1, t2)); } /** * Converts three items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param t3 * third item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2, T t3) { return from(Arrays.asList(t1, t2, t3)); } /** * Converts four items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param t3 * third item * @param t4 * fourth item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2, T t3, T t4) { return from(Arrays.asList(t1, t2, t3, t4)); } /** * Converts five items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param t3 * third item * @param t4 * fourth item * @param t5 * fifth item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2, T t3, T t4, T t5) { return from(Arrays.asList(t1, t2, t3, t4, t5)); } /** * Converts six items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param t3 * third item * @param t4 * fourth item * @param t5 * fifth item * @param t6 * sixth item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2, T t3, T t4, T t5, T t6) { return from(Arrays.asList(t1, t2, t3, t4, t5, t6)); } /** * Converts seven items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param t3 * third item * @param t4 * fourth item * @param t5 * fifth item * @param t6 * sixth item * @param t7 * seventh item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2, T t3, T t4, T t5, T t6, T t7) { return from(Arrays.asList(t1, t2, t3, t4, t5, t6, t7)); } /** * Converts eight items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param t3 * third item * @param t4 * fourth item * @param t5 * fifth item * @param t6 * sixth item * @param t7 * seventh item * @param t8 * eighth item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2, T t3, T t4, T t5, T t6, T t7, T t8) { return from(Arrays.asList(t1, t2, t3, t4, t5, t6, t7, t8)); } /** * Converts nine items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param t3 * third item * @param t4 * fourth item * @param t5 * fifth item * @param t6 * sixth item * @param t7 * seventh item * @param t8 * eighth item * @param t9 * ninth item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2, T t3, T t4, T t5, T t6, T t7, T t8, T t9) { return from(Arrays.asList(t1, t2, t3, t4, t5, t6, t7, t8, t9)); } /** * Converts ten items into an Observable that emits those items. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/just.m.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code just} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * first item * @param t2 * second item * @param t3 * third item * @param t4 * fourth item * @param t5 * fifth item * @param t6 * sixth item * @param t7 * seventh item * @param t8 * eighth item * @param t9 * ninth item * @param t10 * tenth item * @param <T> * the type of these items * @return an Observable that emits each item * @see <a href="http://reactivex.io/documentation/operators/just.html">ReactiveX operators documentation: Just</a> */ // suppress unchecked because we are using varargs inside the method @SuppressWarnings("unchecked") public final static <T> Observable<T> just(T t1, T t2, T t3, T t4, T t5, T t6, T t7, T t8, T t9, T t10) { return from(Arrays.asList(t1, t2, t3, t4, t5, t6, t7, t8, t9, t10)); } /** * Flattens an Iterable of Observables into one Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine the items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param sequences * the Iterable of Observables * @return an Observable that emits items that are the result of flattening the items emitted by the * Observables in the Iterable * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> merge(Iterable<? extends Observable<? extends T>> sequences) { return merge(from(sequences)); } /** * Flattens an Iterable of Observables into one Observable, without any transformation, while limiting the * number of concurrent subscriptions to these Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine the items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param sequences * the Iterable of Observables * @param maxConcurrent * the maximum number of Observables that may be subscribed to concurrently * @return an Observable that emits items that are the result of flattening the items emitted by the * Observables in the Iterable * @throws IllegalArgumentException * if {@code maxConcurrent} is less than or equal to 0 * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> merge(Iterable<? extends Observable<? extends T>> sequences, int maxConcurrent) { return merge(from(sequences), maxConcurrent); } /** * Flattens an Observable that emits Observables into a single Observable that emits the items emitted by * those Observables, without any transformation. * <p> * <img width="640" height="370" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.oo.png" alt=""> * <p> * You can combine the items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param source * an Observable that emits Observables * @return an Observable that emits items that are the result of flattening the Observables emitted by the * {@code source} Observable * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> merge(Observable<? extends Observable<? extends T>> source) { return source.lift(OperatorMerge.<T>instance(false)); } /** * Flattens an Observable that emits Observables into a single Observable that emits the items emitted by * those Observables, without any transformation, while limiting the maximum number of concurrent * subscriptions to these Observables. * <p> * <img width="640" height="370" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.oo.png" alt=""> * <p> * You can combine the items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param source * an Observable that emits Observables * @param maxConcurrent * the maximum number of Observables that may be subscribed to concurrently * @return an Observable that emits items that are the result of flattening the Observables emitted by the * {@code source} Observable * @throws IllegalArgumentException * if {@code maxConcurrent} is less than or equal to 0 * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> merge(Observable<? extends Observable<? extends T>> source, int maxConcurrent) { return source.lift(new OperatorMergeMaxConcurrent<T>(maxConcurrent)); } /** * Flattens two Observables into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> merge(Observable<? extends T> t1, Observable<? extends T> t2) { return merge(from(Arrays.asList(t1, t2))); } /** * Flattens three Observables into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> merge(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3) { return merge(from(Arrays.asList(t1, t2, t3))); } /** * Flattens four Observables into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> merge(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4) { return merge(from(Arrays.asList(t1, t2, t3, t4))); } /** * Flattens five Observables into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> merge(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5) { return merge(from(Arrays.asList(t1, t2, t3, t4, t5))); } /** * Flattens six Observables into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @param t6 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> merge(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6) { return merge(from(Arrays.asList(t1, t2, t3, t4, t5, t6))); } /** * Flattens seven Observables into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @param t6 * an Observable to be merged * @param t7 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> merge(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7) { return merge(from(Arrays.asList(t1, t2, t3, t4, t5, t6, t7))); } /** * Flattens eight Observables into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @param t6 * an Observable to be merged * @param t7 * an Observable to be merged * @param t8 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> merge(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7, Observable<? extends T> t8) { return merge(from(Arrays.asList(t1, t2, t3, t4, t5, t6, t7, t8))); } /** * Flattens nine Observables into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @param t6 * an Observable to be merged * @param t7 * an Observable to be merged * @param t8 * an Observable to be merged * @param t9 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ @SuppressWarnings("unchecked") public final static <T> Observable<T> merge(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7, Observable<? extends T> t8, Observable<? extends T> t9) { return merge(from(Arrays.asList(t1, t2, t3, t4, t5, t6, t7, t8, t9))); } /** * Flattens an Array of Observables into one Observable, without any transformation. * <p> * <img width="640" height="370" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.io.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code merge} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code merge} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param sequences * the Array of Observables * @return an Observable that emits all of the items emitted by the Observables in the Array * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> merge(Observable<? extends T>[] sequences) { return merge(from(sequences)); } /** * Flattens an Observable that emits Observables into one Observable, in a way that allows an Observer to * receive all successfully emitted items from all of the source Observables without being interrupted by * an error notification from one of them. * <p> * This behaves like {@link #merge(Observable)} except that if any of the merged Observables notify of an * error via {@link Observer#onError onError}, {@code mergeDelayError} will refrain from propagating that * error notification until all of the merged Observables have finished emitting items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if multiple merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param source * an Observable that emits Observables * @return an Observable that emits all of the items emitted by the Observables emitted by the * {@code source} Observable * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> mergeDelayError(Observable<? extends Observable<? extends T>> source) { return source.lift(OperatorMerge.<T>instance(true)); } /** * Flattens two Observables into one Observable, in a way that allows an Observer to receive all * successfully emitted items from each of the source Observables without being interrupted by an error * notification from one of them. * <p> * This behaves like {@link #merge(Observable, Observable)} except that if any of the merged Observables * notify of an error via {@link Observer#onError onError}, {@code mergeDelayError} will refrain from * propagating that error notification until all of the merged Observables have finished emitting items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if both merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @return an Observable that emits all of the items that are emitted by the two source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> mergeDelayError(Observable<? extends T> t1, Observable<? extends T> t2) { return mergeDelayError(just(t1, t2)); } /** * Flattens three Observables into one Observable, in a way that allows an Observer to receive all * successfully emitted items from all of the source Observables without being interrupted by an error * notification from one of them. * <p> * This behaves like {@link #merge(Observable, Observable, Observable)} except that if any of the merged * Observables notify of an error via {@link Observer#onError onError}, {@code mergeDelayError} will refrain * from propagating that error notification until all of the merged Observables have finished emitting * items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if multiple merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @return an Observable that emits all of the items that are emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> mergeDelayError(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3) { return mergeDelayError(just(t1, t2, t3)); } /** * Flattens four Observables into one Observable, in a way that allows an Observer to receive all * successfully emitted items from all of the source Observables without being interrupted by an error * notification from one of them. * <p> * This behaves like {@link #merge(Observable, Observable, Observable, Observable)} except that if any of * the merged Observables notify of an error via {@link Observer#onError onError}, {@code mergeDelayError} * will refrain from propagating that error notification until all of the merged Observables have finished * emitting items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if multiple merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @return an Observable that emits all of the items that are emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> mergeDelayError(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4) { return mergeDelayError(just(t1, t2, t3, t4)); } /** * Flattens five Observables into one Observable, in a way that allows an Observer to receive all * successfully emitted items from all of the source Observables without being interrupted by an error * notification from one of them. * <p> * This behaves like {@link #merge(Observable, Observable, Observable, Observable, Observable)} except that * if any of the merged Observables notify of an error via {@link Observer#onError onError}, * {@code mergeDelayError} will refrain from propagating that error notification until all of the merged * Observables have finished emitting items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if multiple merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @return an Observable that emits all of the items that are emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> mergeDelayError(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5) { return mergeDelayError(just(t1, t2, t3, t4, t5)); } /** * Flattens six Observables into one Observable, in a way that allows an Observer to receive all * successfully emitted items from all of the source Observables without being interrupted by an error * notification from one of them. * <p> * This behaves like {@link #merge(Observable, Observable, Observable, Observable, Observable, Observable)} * except that if any of the merged Observables notify of an error via {@link Observer#onError onError}, * {@code mergeDelayError} will refrain from propagating that error notification until all of the merged * Observables have finished emitting items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if multiple merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @param t6 * an Observable to be merged * @return an Observable that emits all of the items that are emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> mergeDelayError(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6) { return mergeDelayError(just(t1, t2, t3, t4, t5, t6)); } /** * Flattens seven Observables into one Observable, in a way that allows an Observer to receive all * successfully emitted items from all of the source Observables without being interrupted by an error * notification from one of them. * <p> * This behaves like * {@link #merge(Observable, Observable, Observable, Observable, Observable, Observable, Observable)} * except that if any of the merged Observables notify of an error via {@link Observer#onError onError}, * {@code mergeDelayError} will refrain from propagating that error notification until all of the merged * Observables have finished emitting items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if multiple merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @param t6 * an Observable to be merged * @param t7 * an Observable to be merged * @return an Observable that emits all of the items that are emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> mergeDelayError(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7) { return mergeDelayError(just(t1, t2, t3, t4, t5, t6, t7)); } /** * Flattens eight Observables into one Observable, in a way that allows an Observer to receive all * successfully emitted items from all of the source Observables without being interrupted by an error * notification from one of them. * <p> * This behaves like {@link #merge(Observable, Observable, Observable, Observable, Observable, Observable, Observable, Observable)} * except that if any of the merged Observables notify of an error via {@link Observer#onError onError}, * {@code mergeDelayError} will refrain from propagating that error notification until all of the merged * Observables have finished emitting items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if multiple merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @param t6 * an Observable to be merged * @param t7 * an Observable to be merged * @param t8 * an Observable to be merged * @return an Observable that emits all of the items that are emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ // suppress because the types are checked by the method signature before using a vararg public final static <T> Observable<T> mergeDelayError(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7, Observable<? extends T> t8) { return mergeDelayError(just(t1, t2, t3, t4, t5, t6, t7, t8)); } /** * Flattens nine Observables into one Observable, in a way that allows an Observer to receive all * successfully emitted items from all of the source Observables without being interrupted by an error * notification from one of them. * <p> * This behaves like {@link #merge(Observable, Observable, Observable, Observable, Observable, Observable, Observable, Observable, Observable)} * except that if any of the merged Observables notify of an error via {@link Observer#onError onError}, * {@code mergeDelayError} will refrain from propagating that error notification until all of the merged * Observables have finished emitting items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeDelayError.png" alt=""> * <p> * Even if multiple merged Observables send {@code onError} notifications, {@code mergeDelayError} will only * invoke the {@code onError} method of its Observers once. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeDelayError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @param t2 * an Observable to be merged * @param t3 * an Observable to be merged * @param t4 * an Observable to be merged * @param t5 * an Observable to be merged * @param t6 * an Observable to be merged * @param t7 * an Observable to be merged * @param t8 * an Observable to be merged * @param t9 * an Observable to be merged * @return an Observable that emits all of the items that are emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final static <T> Observable<T> mergeDelayError(Observable<? extends T> t1, Observable<? extends T> t2, Observable<? extends T> t3, Observable<? extends T> t4, Observable<? extends T> t5, Observable<? extends T> t6, Observable<? extends T> t7, Observable<? extends T> t8, Observable<? extends T> t9) { return mergeDelayError(just(t1, t2, t3, t4, t5, t6, t7, t8, t9)); } /** * Converts the source {@code Observable<T>} into an {@code Observable<Observable<T>>} that emits the * source Observable as its single emission. * <p> * <img width="640" height="350" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/nest.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code nest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits a single item: the source Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final Observable<Observable<T>> nest() { return just(this); } /** * Returns an Observable that never sends any items or notifications to an {@link Observer}. * <p> * <img width="640" height="185" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/never.png" alt=""> * <p> * This Observable is useful primarily for testing purposes. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code never} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <T> * the type of items (not) emitted by the Observable * @return an Observable that never emits any items or sends any notifications to an {@link Observer} * @see <a href="http://reactivex.io/documentation/operators/empty-never-throw.html">ReactiveX operators documentation: Never</a> */ public final static <T> Observable<T> never() { return new NeverObservable<T>(); } /** * Returns an Observable that emits a sequence of Integers within a specified range. * <p> * <img width="640" height="195" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/range.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code range} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param start * the value of the first Integer in the sequence * @param count * the number of sequential Integers to generate * @return an Observable that emits a range of sequential Integers * @throws IllegalArgumentException * if {@code count} is less than zero, or if {@code start} + {@code count} − 1 exceeds * {@code Integer.MAX_VALUE} * @see <a href="http://reactivex.io/documentation/operators/range.html">ReactiveX operators documentation: Range</a> */ public final static Observable<Integer> range(int start, int count) { if (count < 0) { throw new IllegalArgumentException("Count can not be negative"); } if (count == 0) { return Observable.empty(); } if (start > Integer.MAX_VALUE - count + 1) { throw new IllegalArgumentException("start + count can not exceed Integer.MAX_VALUE"); } if(count == 1) { return Observable.just(start); } return Observable.create(new OnSubscribeRange(start, start + (count - 1))); } /** * Returns an Observable that emits a sequence of Integers within a specified range, on a specified * Scheduler. * <p> * <img width="640" height="195" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/range.s.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param start * the value of the first Integer in the sequence * @param count * the number of sequential Integers to generate * @param scheduler * the Scheduler to run the generator loop on * @return an Observable that emits a range of sequential Integers * @see <a href="http://reactivex.io/documentation/operators/range.html">ReactiveX operators documentation: Range</a> */ public final static Observable<Integer> range(int start, int count, Scheduler scheduler) { return range(start, count).subscribeOn(scheduler); } /** * Returns an Observable that emits a Boolean value that indicates whether two Observable sequences are the * same by comparing the items emitted by each Observable pairwise. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sequenceEqual.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code sequenceEqual} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param first * the first Observable to compare * @param second * the second Observable to compare * @param <T> * the type of items emitted by each Observable * @return an Observable that emits a Boolean value that indicates whether the two sequences are the same * @see <a href="http://reactivex.io/documentation/operators/sequenceequal.html">ReactiveX operators documentation: SequenceEqual</a> */ public final static <T> Observable<Boolean> sequenceEqual(Observable<? extends T> first, Observable<? extends T> second) { return sequenceEqual(first, second, new Func2<T, T, Boolean>() { @Override public final Boolean call(T first, T second) { if (first == null) { return second == null; } return first.equals(second); } }); } /** * Returns an Observable that emits a Boolean value that indicates whether two Observable sequences are the * same by comparing the items emitted by each Observable pairwise based on the results of a specified * equality function. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sequenceEqual.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code sequenceEqual} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param first * the first Observable to compare * @param second * the second Observable to compare * @param equality * a function used to compare items emitted by each Observable * @param <T> * the type of items emitted by each Observable * @return an Observable that emits a Boolean value that indicates whether the two Observable two sequences * are the same according to the specified function * @see <a href="http://reactivex.io/documentation/operators/sequenceequal.html">ReactiveX operators documentation: SequenceEqual</a> */ public final static <T> Observable<Boolean> sequenceEqual(Observable<? extends T> first, Observable<? extends T> second, Func2<? super T, ? super T, Boolean> equality) { return OperatorSequenceEqual.sequenceEqual(first, second, equality); } /** * Converts an Observable that emits Observables into an Observable that emits the items emitted by the * most recently emitted of those Observables. * <p> * <img width="640" height="370" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/switchDo.png" alt=""> * <p> * {@code switchOnNext} subscribes to an Observable that emits Observables. Each time it observes one of * these emitted Observables, the Observable returned by {@code switchOnNext} begins emitting the items * emitted by that Observable. When a new Observable is emitted, {@code switchOnNext} stops emitting items * from the earlier-emitted Observable and begins emitting items from the new one. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code switchOnNext} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <T> the item type * @param sequenceOfSequences * the source Observable that emits Observables * @return an Observable that emits the items emitted by the Observable most recently emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/switch.html">ReactiveX operators documentation: Switch</a> */ public final static <T> Observable<T> switchOnNext(Observable<? extends Observable<? extends T>> sequenceOfSequences) { return sequenceOfSequences.lift(OperatorSwitch.<T>instance()); } /** * Returns an Observable that emits a {@code 0L} after the {@code initialDelay} and ever increasing numbers * after each {@code period} of time thereafter. * <p> * <img width="640" height="200" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timer.p.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. If the downstream needs a slower rate * it should slow the timer or use something like {@link #onBackpressureDrop}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code timer} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param initialDelay * the initial delay time to wait before emitting the first value of 0L * @param period * the period of time between emissions of the subsequent numbers * @param unit * the time unit for both {@code initialDelay} and {@code period} * @return an Observable that emits a 0L after the {@code initialDelay} and ever increasing numbers after * each {@code period} of time thereafter * @see <a href="http://reactivex.io/documentation/operators/timer.html">ReactiveX operators documentation: Timer</a> */ public final static Observable<Long> timer(long initialDelay, long period, TimeUnit unit) { return timer(initialDelay, period, unit, Schedulers.computation()); } /** * Returns an Observable that emits a {@code 0L} after the {@code initialDelay} and ever increasing numbers * after each {@code period} of time thereafter, on a specified {@link Scheduler}. * <p> * <img width="640" height="200" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timer.ps.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. If the downstream needs a slower rate * it should slow the timer or use something like {@link #onBackpressureDrop}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param initialDelay * the initial delay time to wait before emitting the first value of 0L * @param period * the period of time between emissions of the subsequent numbers * @param unit * the time unit for both {@code initialDelay} and {@code period} * @param scheduler * the Scheduler on which the waiting happens and items are emitted * @return an Observable that emits a 0L after the {@code initialDelay} and ever increasing numbers after * each {@code period} of time thereafter, while running on the given Scheduler * @see <a href="http://reactivex.io/documentation/operators/timer.html">ReactiveX operators documentation: Timer</a> */ public final static Observable<Long> timer(long initialDelay, long period, TimeUnit unit, Scheduler scheduler) { return create(new OnSubscribeTimerPeriodically(initialDelay, period, unit, scheduler)); } /** * Returns an Observable that emits one item after a specified delay, and then completes. * <p> * <img width="640" height="200" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timer.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. If the downstream needs a slower rate * it should slow the timer or use something like {@link #onBackpressureDrop}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code timer} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param delay * the initial delay before emitting a single {@code 0L} * @param unit * time units to use for {@code delay} * @return an Observable that emits one item after a specified delay, and then completes * @see <a href="http://reactivex.io/documentation/operators/timer.html">ReactiveX operators documentation: Timer</a> */ public final static Observable<Long> timer(long delay, TimeUnit unit) { return timer(delay, unit, Schedulers.computation()); } /** * Returns an Observable that emits one item after a specified delay, on a specified Scheduler, and then * completes. * <p> * <img width="640" height="200" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timer.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. If the downstream needs a slower rate * it should slow the timer or use something like {@link #onBackpressureDrop}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param delay * the initial delay before emitting a single 0L * @param unit * time units to use for {@code delay} * @param scheduler * the {@link Scheduler} to use for scheduling the item * @return an Observable that emits one item after a specified delay, on a specified Scheduler, and then * completes * @see <a href="http://reactivex.io/documentation/operators/timer.html">ReactiveX operators documentation: Timer</a> */ public final static Observable<Long> timer(long delay, TimeUnit unit, Scheduler scheduler) { return create(new OnSubscribeTimerOnce(delay, unit, scheduler)); } /** * Constructs an Observable that creates a dependent resource object which is disposed of on unsubscription. * <p> * <img width="640" height="400" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/using.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code using} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param resourceFactory * the factory function to create a resource object that depends on the Observable * @param observableFactory * the factory function to create an Observable * @param disposeAction * the function that will dispose of the resource * @return the Observable whose lifetime controls the lifetime of the dependent resource object * @see <a href="http://reactivex.io/documentation/operators/using.html">ReactiveX operators documentation: Using</a> */ public final static <T, Resource> Observable<T> using( final Func0<Resource> resourceFactory, final Func1<? super Resource, ? extends Observable<? extends T>> observableFactory, final Action1<? super Resource> disposeAction) { return using(resourceFactory, observableFactory, disposeAction, false); } /** * Constructs an Observable that creates a dependent resource object which is disposed of just before * termination if you have set {@code disposeEagerly} to {@code true} and unsubscription does not occur * before termination. Otherwise resource disposal will occur on unsubscription. Eager disposal is * particularly appropriate for a synchronous Observable that resuses resources. {@code disposeAction} will * only be called once per subscription. * <p> * <img width="640" height="400" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/using.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code using} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @warn "Backpressure Support" section missing from javadoc * @param resourceFactory * the factory function to create a resource object that depends on the Observable * @param observableFactory * the factory function to create an Observable * @param disposeAction * the function that will dispose of the resource * @param disposeEagerly * if {@code true} then disposal will happen either on unsubscription or just before emission of * a terminal event ({@code onComplete} or {@code onError}). * @return the Observable whose lifetime controls the lifetime of the dependent resource object * @see <a href="http://reactivex.io/documentation/operators/using.html">ReactiveX operators documentation: Using</a> * @Experimental The behavior of this can change at any time. * @since (if this graduates from Experimental/Beta to supported, replace * this parenthetical with the release number) */ @Experimental public final static <T, Resource> Observable<T> using( final Func0<Resource> resourceFactory, final Func1<? super Resource, ? extends Observable<? extends T>> observableFactory, final Action1<? super Resource> disposeAction, boolean disposeEagerly) { return create(new OnSubscribeUsing<T, Resource>(resourceFactory, observableFactory, disposeAction, disposeEagerly)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * items emitted, in sequence, by an Iterable of other Observables. * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by each of the source Observables; * the second item emitted by the new Observable will be the result of the function applied to the second * item emitted by each of those Observables; and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@code onNext} as many times as * the number of {@code onNext} invokations of the source Observable that emits the fewest items. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param ws * an Iterable of source Observables * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results in * an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <R> Observable<R> zip(Iterable<? extends Observable<?>> ws, FuncN<? extends R> zipFunction) { List<Observable<?>> os = new ArrayList<Observable<?>>(); for (Observable<?> o : ws) { os.add(o); } return Observable.just(os.toArray(new Observable<?>[os.size()])).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * <i>n</i> items emitted, in sequence, by the <i>n</i> Observables emitted by a specified Observable. * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by each of the Observables emitted * by the source Observable; the second item emitted by the new Observable will be the result of the * function applied to the second item emitted by each of those Observables; and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@code onNext} as many times as * the number of {@code onNext} invokations of the source Observable that emits the fewest items. * <p> * <img width="640" height="370" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.o.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param ws * an Observable of source Observables * @param zipFunction * a function that, when applied to an item emitted by each of the Observables emitted by * {@code ws}, results in an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <R> Observable<R> zip(Observable<? extends Observable<?>> ws, final FuncN<? extends R> zipFunction) { return ws.toList().map(new Func1<List<? extends Observable<?>>, Observable<?>[]>() { @Override public Observable<?>[] call(List<? extends Observable<?>> o) { return o.toArray(new Observable<?>[o.size()]); } }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * two items emitted, in sequence, by two other Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by {@code o1} and the first item * emitted by {@code o2}; the second item emitted by the new Observable will be the result of the function * applied to the second item emitted by {@code o1} and the second item emitted by {@code o2}; and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@link Observer#onNext onNext} * as many times as the number of {@code onNext} invocations of the source Observable that emits the fewest * items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * a second source Observable * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results * in an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <T1, T2, R> Observable<R> zip(Observable<? extends T1> o1, Observable<? extends T2> o2, final Func2<? super T1, ? super T2, ? extends R> zipFunction) { return just(new Observable<?>[] { o1, o2 }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * three items emitted, in sequence, by three other Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by {@code o1}, the first item * emitted by {@code o2}, and the first item emitted by {@code o3}; the second item emitted by the new * Observable will be the result of the function applied to the second item emitted by {@code o1}, the * second item emitted by {@code o2}, and the second item emitted by {@code o3}; and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@link Observer#onNext onNext} * as many times as the number of {@code onNext} invocations of the source Observable that emits the fewest * items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * a second source Observable * @param o3 * a third source Observable * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results in * an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <T1, T2, T3, R> Observable<R> zip(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Func3<? super T1, ? super T2, ? super T3, ? extends R> zipFunction) { return just(new Observable<?>[] { o1, o2, o3 }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * four items emitted, in sequence, by four other Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by {@code o1}, the first item * emitted by {@code o2}, the first item emitted by {@code o3}, and the first item emitted by {@code 04}; * the second item emitted by the new Observable will be the result of the function applied to the second * item emitted by each of those Observables; and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@link Observer#onNext onNext} * as many times as the number of {@code onNext} invocations of the source Observable that emits the fewest * items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * a second source Observable * @param o3 * a third source Observable * @param o4 * a fourth source Observable * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results in * an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <T1, T2, T3, T4, R> Observable<R> zip(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Func4<? super T1, ? super T2, ? super T3, ? super T4, ? extends R> zipFunction) { return just(new Observable<?>[] { o1, o2, o3, o4 }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * five items emitted, in sequence, by five other Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by {@code o1}, the first item * emitted by {@code o2}, the first item emitted by {@code o3}, the first item emitted by {@code o4}, and * the first item emitted by {@code o5}; the second item emitted by the new Observable will be the result of * the function applied to the second item emitted by each of those Observables; and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@link Observer#onNext onNext} * as many times as the number of {@code onNext} invocations of the source Observable that emits the fewest * items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * a second source Observable * @param o3 * a third source Observable * @param o4 * a fourth source Observable * @param o5 * a fifth source Observable * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results in * an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <T1, T2, T3, T4, T5, R> Observable<R> zip(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Func5<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? extends R> zipFunction) { return just(new Observable<?>[] { o1, o2, o3, o4, o5 }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * six items emitted, in sequence, by six other Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by each source Observable, the * second item emitted by the new Observable will be the result of the function applied to the second item * emitted by each of those Observables, and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@link Observer#onNext onNext} * as many times as the number of {@code onNext} invocations of the source Observable that emits the fewest * items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * a second source Observable * @param o3 * a third source Observable * @param o4 * a fourth source Observable * @param o5 * a fifth source Observable * @param o6 * a sixth source Observable * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results in * an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <T1, T2, T3, T4, T5, T6, R> Observable<R> zip(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Func6<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? extends R> zipFunction) { return just(new Observable<?>[] { o1, o2, o3, o4, o5, o6 }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * seven items emitted, in sequence, by seven other Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by each source Observable, the * second item emitted by the new Observable will be the result of the function applied to the second item * emitted by each of those Observables, and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@link Observer#onNext onNext} * as many times as the number of {@code onNext} invocations of the source Observable that emits the fewest * items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * a second source Observable * @param o3 * a third source Observable * @param o4 * a fourth source Observable * @param o5 * a fifth source Observable * @param o6 * a sixth source Observable * @param o7 * a seventh source Observable * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results in * an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <T1, T2, T3, T4, T5, T6, T7, R> Observable<R> zip(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7, Func7<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? extends R> zipFunction) { return just(new Observable<?>[] { o1, o2, o3, o4, o5, o6, o7 }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * eight items emitted, in sequence, by eight other Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by each source Observable, the * second item emitted by the new Observable will be the result of the function applied to the second item * emitted by each of those Observables, and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@link Observer#onNext onNext} * as many times as the number of {@code onNext} invocations of the source Observable that emits the fewest * items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * a second source Observable * @param o3 * a third source Observable * @param o4 * a fourth source Observable * @param o5 * a fifth source Observable * @param o6 * a sixth source Observable * @param o7 * a seventh source Observable * @param o8 * an eighth source Observable * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results in * an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <T1, T2, T3, T4, T5, T6, T7, T8, R> Observable<R> zip(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7, Observable<? extends T8> o8, Func8<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? super T8, ? extends R> zipFunction) { return just(new Observable<?>[] { o1, o2, o3, o4, o5, o6, o7, o8 }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits the results of a specified combiner function applied to combinations of * nine items emitted, in sequence, by nine other Observables. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <p> * {@code zip} applies this function in strict sequence, so the first item emitted by the new Observable * will be the result of the function applied to the first item emitted by each source Observable, the * second item emitted by the new Observable will be the result of the function applied to the second item * emitted by each of those Observables, and so forth. * <p> * The resulting {@code Observable<R>} returned from {@code zip} will invoke {@link Observer#onNext onNext} * as many times as the number of {@code onNext} invocations of the source Observable that emits the fewest * items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param o1 * the first source Observable * @param o2 * a second source Observable * @param o3 * a third source Observable * @param o4 * a fourth source Observable * @param o5 * a fifth source Observable * @param o6 * a sixth source Observable * @param o7 * a seventh source Observable * @param o8 * an eighth source Observable * @param o9 * a ninth source Observable * @param zipFunction * a function that, when applied to an item emitted by each of the source Observables, results in * an item that will be emitted by the resulting Observable * @return an Observable that emits the zipped results * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final static <T1, T2, T3, T4, T5, T6, T7, T8, T9, R> Observable<R> zip(Observable<? extends T1> o1, Observable<? extends T2> o2, Observable<? extends T3> o3, Observable<? extends T4> o4, Observable<? extends T5> o5, Observable<? extends T6> o6, Observable<? extends T7> o7, Observable<? extends T8> o8, Observable<? extends T9> o9, Func9<? super T1, ? super T2, ? super T3, ? super T4, ? super T5, ? super T6, ? super T7, ? super T8, ? super T9, ? extends R> zipFunction) { return just(new Observable<?>[] { o1, o2, o3, o4, o5, o6, o7, o8, o9 }).lift(new OperatorZip<R>(zipFunction)); } /** * Returns an Observable that emits a Boolean that indicates whether all of the items emitted by the source * Observable satisfy a condition. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/all.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code all} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * a function that evaluates an item and returns a Boolean * @return an Observable that emits {@code true} if all items emitted by the source Observable satisfy the * predicate; otherwise, {@code false} * @see <a href="http://reactivex.io/documentation/operators/all.html">ReactiveX operators documentation: All</a> */ public final Observable<Boolean> all(Func1<? super T, Boolean> predicate) { return lift(new OperatorAll<T>(predicate)); } /** * Mirrors the Observable (current or provided) that first either emits an item or sends a termination * notification. * <p> * <img width="640" height="385" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/amb.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code amb} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable competing to react first * @return an Observable that emits the same sequence as whichever of the source Observables first * emitted an item or sent a termination notification * @see <a href="http://reactivex.io/documentation/operators/amb.html">ReactiveX operators documentation: Amb</a> */ public final Observable<T> ambWith(Observable<? extends T> t1) { return amb(this, t1); } /** * Portrays a object of an Observable subclass as a simple Observable object. This is useful, for instance, * when you have an implementation of a subclass of Observable but you want to hide the properties and * methods of this subclass from whomever you are passing the Observable to. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code asObservable} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that hides the identity of this Observable */ public final Observable<T> asObservable() { return lift(OperatorAsObservable.<T>instance()); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping buffers. It emits the current buffer and replaces it with a * new buffer whenever the Observable produced by the specified {@code bufferClosingSelector} emits an item. * <p> * <img width="640" height="395" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer1.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it is instead controlled by the given Observables and * buffers data. It requests {@code Long.MAX_VALUE} upstream and does not obey downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param bufferClosingSelector * a {@link Func0} that produces an Observable that governs the boundary between buffers. * Whenever this {@code Observable} emits an item, {@code buffer} emits the current buffer and * begins to fill a new one * @return an Observable that emits a connected, non-overlapping buffer of items from the source Observable * each time the Observable created with the {@code bufferClosingSelector} argument emits an item * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final <TClosing> Observable<List<T>> buffer(Func0<? extends Observable<? extends TClosing>> bufferClosingSelector) { return lift(new OperatorBufferWithSingleObservable<T, TClosing>(bufferClosingSelector, 16)); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping buffers, each containing {@code count} items. When the source * Observable completes or encounters an error, the resulting Observable emits the current buffer and * propagates the notification from the source Observable. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer3.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param count * the maximum number of items in each buffer before it should be emitted * @return an Observable that emits connected, non-overlapping buffers, each containing at most * {@code count} items from the source Observable * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final Observable<List<T>> buffer(int count) { return buffer(count, count); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable emits buffers every {@code skip} items, each containing {@code count} items. When the source * Observable completes or encounters an error, the resulting Observable emits the current buffer and * propagates the notification from the source Observable. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer4.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param count * the maximum size of each buffer before it should be emitted * @param skip * how many items emitted by the source Observable should be skipped before starting a new * buffer. Note that when {@code skip} and {@code count} are equal, this is the same operation as * {@link #buffer(int)}. * @return an Observable that emits buffers for every {@code skip} item from the source Observable and * containing at most {@code count} items * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final Observable<List<T>> buffer(int count, int skip) { return lift(new OperatorBufferWithSize<T>(count, skip)); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable starts a new buffer periodically, as determined by the {@code timeshift} argument. It emits * each buffer after a fixed timespan, specified by the {@code timespan} argument. When the source * Observable completes or encounters an error, the resulting Observable emits the current buffer and * propagates the notification from the source Observable. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer7.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. It requests {@code Long.MAX_VALUE} * upstream and does not obey downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timespan * the period of time each buffer collects items before it is emitted * @param timeshift * the period of time after which a new buffer will be created * @param unit * the unit of time that applies to the {@code timespan} and {@code timeshift} arguments * @return an Observable that emits new buffers of items emitted by the source Observable periodically after * a fixed timespan has elapsed * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final Observable<List<T>> buffer(long timespan, long timeshift, TimeUnit unit) { return buffer(timespan, timeshift, unit, Schedulers.computation()); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable starts a new buffer periodically, as determined by the {@code timeshift} argument, and on the * specified {@code scheduler}. It emits each buffer after a fixed timespan, specified by the * {@code timespan} argument. When the source Observable completes or encounters an error, the resulting * Observable emits the current buffer and propagates the notification from the source Observable. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer7.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. It requests {@code Long.MAX_VALUE} * upstream and does not obey downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timespan * the period of time each buffer collects items before it is emitted * @param timeshift * the period of time after which a new buffer will be created * @param unit * the unit of time that applies to the {@code timespan} and {@code timeshift} arguments * @param scheduler * the {@link Scheduler} to use when determining the end and start of a buffer * @return an Observable that emits new buffers of items emitted by the source Observable periodically after * a fixed timespan has elapsed * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final Observable<List<T>> buffer(long timespan, long timeshift, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorBufferWithTime<T>(timespan, timeshift, unit, Integer.MAX_VALUE, scheduler)); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping buffers, each of a fixed duration specified by the * {@code timespan} argument. When the source Observable completes or encounters an error, the resulting * Observable emits the current buffer and propagates the notification from the source Observable. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer5.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. It requests {@code Long.MAX_VALUE} * upstream and does not obey downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timespan * the period of time each buffer collects items before it is emitted and replaced with a new * buffer * @param unit * the unit of time that applies to the {@code timespan} argument * @return an Observable that emits connected, non-overlapping buffers of items emitted by the source * Observable within a fixed duration * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final Observable<List<T>> buffer(long timespan, TimeUnit unit) { return buffer(timespan, unit, Integer.MAX_VALUE, Schedulers.computation()); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping buffers, each of a fixed duration specified by the * {@code timespan} argument or a maximum size specified by the {@code count} argument (whichever is reached * first). When the source Observable completes or encounters an error, the resulting Observable emits the * current buffer and propagates the notification from the source Observable. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer6.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. It requests {@code Long.MAX_VALUE} * upstream and does not obey downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timespan * the period of time each buffer collects items before it is emitted and replaced with a new * buffer * @param unit * the unit of time which applies to the {@code timespan} argument * @param count * the maximum size of each buffer before it is emitted * @return an Observable that emits connected, non-overlapping buffers of items emitted by the source * Observable, after a fixed duration or when the buffer reaches maximum capacity (whichever occurs * first) * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final Observable<List<T>> buffer(long timespan, TimeUnit unit, int count) { return lift(new OperatorBufferWithTime<T>(timespan, timespan, unit, count, Schedulers.computation())); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping buffers, each of a fixed duration specified by the * {@code timespan} argument as measured on the specified {@code scheduler}, or a maximum size specified by * the {@code count} argument (whichever is reached first). When the source Observable completes or * encounters an error, the resulting Observable emits the current buffer and propagates the notification * from the source Observable. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer6.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. It requests {@code Long.MAX_VALUE} * upstream and does not obey downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timespan * the period of time each buffer collects items before it is emitted and replaced with a new * buffer * @param unit * the unit of time which applies to the {@code timespan} argument * @param count * the maximum size of each buffer before it is emitted * @param scheduler * the {@link Scheduler} to use when determining the end and start of a buffer * @return an Observable that emits connected, non-overlapping buffers of items emitted by the source * Observable after a fixed duration or when the buffer reaches maximum capacity (whichever occurs * first) * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final Observable<List<T>> buffer(long timespan, TimeUnit unit, int count, Scheduler scheduler) { return lift(new OperatorBufferWithTime<T>(timespan, timespan, unit, count, scheduler)); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping buffers, each of a fixed duration specified by the * {@code timespan} argument and on the specified {@code scheduler}. When the source Observable completes or * encounters an error, the resulting Observable emits the current buffer and propagates the notification * from the source Observable. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer5.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time. It requests {@code Long.MAX_VALUE} * upstream and does not obey downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timespan * the period of time each buffer collects items before it is emitted and replaced with a new * buffer * @param unit * the unit of time which applies to the {@code timespan} argument * @param scheduler * the {@link Scheduler} to use when determining the end and start of a buffer * @return an Observable that emits connected, non-overlapping buffers of items emitted by the source * Observable within a fixed duration * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final Observable<List<T>> buffer(long timespan, TimeUnit unit, Scheduler scheduler) { return buffer(timespan, timespan, unit, scheduler); } /** * Returns an Observable that emits buffers of items it collects from the source Observable. The resulting * Observable emits buffers that it creates when the specified {@code bufferOpenings} Observable emits an * item, and closes when the Observable returned from {@code bufferClosingSelector} emits an item. * <p> * <img width="640" height="470" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer2.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it is instead controlled by the given Observables and * buffers data. It requests {@code Long.MAX_VALUE} upstream and does not obey downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param bufferOpenings * the Observable that, when it emits an item, causes a new buffer to be created * @param bufferClosingSelector * the {@link Func1} that is used to produce an Observable for every buffer created. When this * Observable emits an item, the associated buffer is emitted. * @return an Observable that emits buffers, containing items from the source Observable, that are created * and closed when the specified Observables emit items * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final <TOpening, TClosing> Observable<List<T>> buffer(Observable<? extends TOpening> bufferOpenings, Func1<? super TOpening, ? extends Observable<? extends TClosing>> bufferClosingSelector) { return lift(new OperatorBufferWithStartEndObservable<T, TOpening, TClosing>(bufferOpenings, bufferClosingSelector)); } /** * Returns an Observable that emits non-overlapping buffered items from the source Observable each time the * specified boundary Observable emits an item. * <p> * <img width="640" height="395" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer8.png" alt=""> * <p> * Completion of either the source or the boundary Observable causes the returned Observable to emit the * latest buffer and complete. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it is instead controlled by the {@code Observable} * {@code boundary} and buffers data. It requests {@code Long.MAX_VALUE} upstream and does not obey * downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <B> * the boundary value type (ignored) * @param boundary * the boundary Observable * @return an Observable that emits buffered items from the source Observable when the boundary Observable * emits an item * @see #buffer(rx.Observable, int) * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> */ public final <B> Observable<List<T>> buffer(Observable<B> boundary) { return buffer(boundary, 16); } /** * Returns an Observable that emits non-overlapping buffered items from the source Observable each time the * specified boundary Observable emits an item. * <p> * <img width="640" height="395" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/buffer8.png" alt=""> * <p> * Completion of either the source or the boundary Observable causes the returned Observable to emit the * latest buffer and complete. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it is instead controlled by the {@code Observable} * {@code boundary} and buffers data. It requests {@code Long.MAX_VALUE} upstream and does not obey * downstream requests.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code buffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <B> * the boundary value type (ignored) * @param boundary * the boundary Observable * @param initialCapacity * the initial capacity of each buffer chunk * @return an Observable that emits buffered items from the source Observable when the boundary Observable * emits an item * @see <a href="http://reactivex.io/documentation/operators/buffer.html">ReactiveX operators documentation: Buffer</a> * @see #buffer(rx.Observable, int) */ public final <B> Observable<List<T>> buffer(Observable<B> boundary, int initialCapacity) { return lift(new OperatorBufferWithSingleObservable<T, B>(boundary, initialCapacity)); } /** * Caches the emissions from the source Observable and replays them in order to any subsequent Subscribers. * This method has similar behavior to {@link #replay} except that this auto-subscribes to the source * Observable rather than returning a {@link ConnectableObservable} for which you must call * {@code connect} to activate the subscription. * <p> * <img width="640" height="410" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/cache.png" alt=""> * <p> * This is useful when you want an Observable to cache responses and you can't control the * subscribe/unsubscribe behavior of all the {@link Subscriber}s. * <p> * When you call {@code cache}, it does not yet subscribe to the source Observable and so does not yet * begin cacheing items. This only happens when the first Subscriber calls the resulting Observable's * {@code subscribe} method. * <p> * <em>Note:</em> You sacrifice the ability to unsubscribe from the origin when you use the {@code cache} * Observer so be careful not to use this Observer on Observables that emit an infinite or very large number * of items that will use up memory. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support upstream backpressure as it is purposefully requesting and caching * everything emitted.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code cache} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that, when first subscribed to, caches all of its items and notifications for the * benefit of subsequent subscribers * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final Observable<T> cache() { return create(new OnSubscribeCache<T>(this)); } /** * Caches emissions from the source Observable and replays them in order to any subsequent Subscribers. * This method has similar behavior to {@link #replay} except that this auto-subscribes to the source * Observable rather than returning a {@link ConnectableObservable} for which you must call * {@code connect} to activate the subscription. * <p> * <img width="640" height="410" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/cache.png" alt=""> * <p> * This is useful when you want an Observable to cache responses and you can't control the * subscribe/unsubscribe behavior of all the {@link Subscriber}s. * <p> * When you call {@code cache}, it does not yet subscribe to the source Observable and so does not yet * begin cacheing items. This only happens when the first Subscriber calls the resulting Observable's * {@code subscribe} method. * <p> * <em>Note:</em> You sacrifice the ability to unsubscribe from the origin when you use the {@code cache} * Observer so be careful not to use this Observer on Observables that emit an infinite or very large number * of items that will use up memory. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support upstream backpressure as it is purposefully requesting and caching * everything emitted.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code cache} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param capacity hint for number of items to cache (for optimizing underlying data structure) * @return an Observable that, when first subscribed to, caches all of its items and notifications for the * benefit of subsequent subscribers * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final Observable<T> cache(int capacity) { return create(new OnSubscribeCache<T>(this, capacity)); } /** * Returns an Observable that emits the items emitted by the source Observable, converted to the specified * type. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/cast.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code cast} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param klass * the target class type that {@code cast} will cast the items emitted by the source Observable * into before emitting them from the resulting Observable * @return an Observable that emits each item from the source Observable after converting it to the * specified type * @see <a href="http://reactivex.io/documentation/operators/map.html">ReactiveX operators documentation: Map</a> */ public final <R> Observable<R> cast(final Class<R> klass) { return lift(new OperatorCast<T, R>(klass)); } /** * Collects items emitted by the source Observable into a single mutable data structure and returns an * Observable that emits this structure. * <p> * <img width="640" height="330" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/collect.png" alt=""> * <p> * This is a simplified version of {@code reduce} that does not need to return the state on each pass. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because by intent it will receive all values and reduce * them to a single {@code onNext}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code collect} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param stateFactory * the mutable data structure that will collect the items * @param collector * a function that accepts the {@code state} and an emitted item, and modifies {@code state} * accordingly * @return an Observable that emits the result of collecting the values emitted by the source Observable * into a single mutable data structure * @see <a href="http://reactivex.io/documentation/operators/reduce.html">ReactiveX operators documentation: Reduce</a> */ public final <R> Observable<R> collect(Func0<R> stateFactory, final Action2<R, ? super T> collector) { Func2<R, T, R> accumulator = new Func2<R, T, R>() { @Override public final R call(R state, T value) { collector.call(state, value); return state; } }; /* * Discussion and confirmation of implementation at * https://github.com/ReactiveX/RxJava/issues/423#issuecomment-27642532 * * It should use last() not takeLast(1) since it needs to emit an error if the sequence is empty. */ return lift(new OperatorScan<R, T>(stateFactory, accumulator)).last(); } /** * Returns a new Observable that emits items resulting from applying a function that you supply to each item * emitted by the source Observable, where that function returns an Observable, and then emitting the items * that result from concatinating those resulting Observables. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concatMap.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concatMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param func * a function that, when applied to an item emitted by the source Observable, returns an * Observable * @return an Observable that emits the result of applying the transformation function to each item emitted * by the source Observable and concatinating the Observables obtained from this transformation * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> */ public final <R> Observable<R> concatMap(Func1<? super T, ? extends Observable<? extends R>> func) { return concat(map(func)); } /** * Returns an Observable that emits the items emitted from the current Observable, then the next, one after * the other, without interleaving them. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/concat.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code concat} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be concatenated after the current * @return an Observable that emits items emitted by the two source Observables, one after the other, * without interleaving them * @see <a href="http://reactivex.io/documentation/operators/concat.html">ReactiveX operators documentation: Concat</a> */ public final Observable<T> concatWith(Observable<? extends T> t1) { return concat(this, t1); } /** * Returns an Observable that emits a Boolean that indicates whether the source Observable emitted a * specified item. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/contains.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code contains} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param element * the item to search for in the emissions from the source Observable * @return an Observable that emits {@code true} if the specified item is emitted by the source Observable, * or {@code false} if the source Observable completes without emitting that item * @see <a href="http://reactivex.io/documentation/operators/contains.html">ReactiveX operators documentation: Contains</a> */ public final Observable<Boolean> contains(final Object element) { return exists(new Func1<T, Boolean>() { @Override public final Boolean call(T t1) { return element == null ? t1 == null : element.equals(t1); } }); } /** * Returns an Observable that emits the count of the total number of items emitted by the source Observable. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/count.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because by intent it will receive all values and reduce * them to a single {@code onNext}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code count} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits a single item: the number of elements emitted by the source Observable * @see <a href="http://reactivex.io/documentation/operators/count.html">ReactiveX operators documentation: Count</a> * @see #countLong() */ public final Observable<Integer> count() { return reduce(0, new Func2<Integer, T, Integer>() { @Override public final Integer call(Integer t1, T t2) { return t1 + 1; } }); } /** * Returns an Observable that counts the total number of items emitted by the source Observable and emits * this count as a 64-bit Long. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/longCount.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because by intent it will receive all values and reduce * them to a single {@code onNext}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code countLong} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits a single item: the number of items emitted by the source Observable as a * 64-bit Long item * @see <a href="http://reactivex.io/documentation/operators/count.html">ReactiveX operators documentation: Count</a> * @see #count() */ public final Observable<Long> countLong() { return reduce(0L, new Func2<Long, T, Long>() { @Override public final Long call(Long t1, T t2) { return t1 + 1; } }); } /** * Returns an Observable that mirrors the source Observable, except that it drops items emitted by the * source Observable that are followed by another item within a computed debounce duration. * <p> * <img width="640" height="425" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/debounce.f.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses the {@code debounceSelector} to mark * boundaries.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code debounce} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <U> * the debounce value type (ignored) * @param debounceSelector * function to retrieve a sequence that indicates the throttle duration for each item * @return an Observable that omits items emitted by the source Observable that are followed by another item * within a computed debounce duration * @see <a href="http://reactivex.io/documentation/operators/debounce.html">ReactiveX operators documentation: Debounce</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> */ public final <U> Observable<T> debounce(Func1<? super T, ? extends Observable<U>> debounceSelector) { return lift(new OperatorDebounceWithSelector<T, U>(debounceSelector)); } /** * Returns an Observable that mirrors the source Observable, except that it drops items emitted by the * source Observable that are followed by newer items before a timeout value expires. The timer resets on * each emission. * <p> * <em>Note:</em> If items keep being emitted by the source Observable faster than the timeout then no items * will be emitted by the resulting Observable. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/debounce.png" alt=""> * <p> * Information on debounce vs throttle: * <p> * <ul> * <li><a href="http://drupalmotion.com/article/debounce-and-throttle-visual-explanation">Debounce and Throttle: visual explanation</a></li> * <li><a href="http://unscriptable.com/2009/03/20/debouncing-javascript-methods/">Debouncing: javascript methods</a></li> * <li><a href="http://www.illyriad.co.uk/blog/index.php/2011/09/javascript-dont-spam-your-server-debounce-and-throttle/">Javascript - don't spam your server: debounce and throttle</a></li> * </ul> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code debounce} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timeout * the time each item has to be "the most recent" of those emitted by the source Observable to * ensure that it's not dropped * @param unit * the {@link TimeUnit} for the timeout * @return an Observable that filters out items from the source Observable that are too quickly followed by * newer items * @see <a href="http://reactivex.io/documentation/operators/debounce.html">ReactiveX operators documentation: Debounce</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> * @see #throttleWithTimeout(long, TimeUnit) */ public final Observable<T> debounce(long timeout, TimeUnit unit) { return debounce(timeout, unit, Schedulers.computation()); } /** * Returns an Observable that mirrors the source Observable, except that it drops items emitted by the * source Observable that are followed by newer items before a timeout value expires on a specified * Scheduler. The timer resets on each emission. * <p> * <em>Note:</em> If items keep being emitted by the source Observable faster than the timeout then no items * will be emitted by the resulting Observable. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/debounce.s.png" alt=""> * <p> * Information on debounce vs throttle: * <p> * <ul> * <li><a href="http://drupalmotion.com/article/debounce-and-throttle-visual-explanation">Debounce and Throttle: visual explanation</a></li> * <li><a href="http://unscriptable.com/2009/03/20/debouncing-javascript-methods/">Debouncing: javascript methods</a></li> * <li><a href="http://www.illyriad.co.uk/blog/index.php/2011/09/javascript-dont-spam-your-server-debounce-and-throttle/">Javascript - don't spam your server: debounce and throttle</a></li> * </ul> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timeout * the time each item has to be "the most recent" of those emitted by the source Observable to * ensure that it's not dropped * @param unit * the unit of time for the specified timeout * @param scheduler * the {@link Scheduler} to use internally to manage the timers that handle the timeout for each * item * @return an Observable that filters out items from the source Observable that are too quickly followed by * newer items * @see <a href="http://reactivex.io/documentation/operators/debounce.html">ReactiveX operators documentation: Debounce</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> * @see #throttleWithTimeout(long, TimeUnit, Scheduler) */ public final Observable<T> debounce(long timeout, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorDebounceWithTime<T>(timeout, unit, scheduler)); } /** * Returns an Observable that emits the items emitted by the source Observable or a specified default item * if the source Observable is empty. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/defaultIfEmpty.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code defaultIfEmpty} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param defaultValue * the item to emit if the source Observable emits no items * @return an Observable that emits either the specified default item if the source Observable emits no * items, or the items emitted by the source Observable * @see <a href="http://reactivex.io/documentation/operators/defaultifempty.html">ReactiveX operators documentation: DefaultIfEmpty</a> */ public final Observable<T> defaultIfEmpty(T defaultValue) { return lift(new OperatorDefaultIfEmpty<T>(defaultValue)); } /** * Returns an Observable that emits the items emitted by the source Observable or the items of an alternate * Observable if the source Observable is empty. * <p/> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code switchIfEmpty} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param alternate * the alternate Observable to subscribe to if the source does not emit any items * @return an Observable that emits the items emitted by the source Observable or the items of an * alternate Observable if the source Observable is empty. * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Experimental public final Observable<T> switchIfEmpty(Observable<? extends T> alternate) { return lift(new OperatorSwitchIfEmpty<T>(alternate)); } /** * Returns an Observable that delays the subscription to and emissions from the souce Observable via another * Observable on a per-item basis. * <p> * <img width="640" height="450" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/delay.oo.png" alt=""> * <p> * <em>Note:</em> the resulting Observable will immediately propagate any {@code onError} notification * from the source Observable. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code delay} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <U> * the subscription delay value type (ignored) * @param <V> * the item delay value type (ignored) * @param subscriptionDelay * a function that returns an Observable that triggers the subscription to the source Observable * once it emits any item * @param itemDelay * a function that returns an Observable for each item emitted by the source Observable, which is * then used to delay the emission of that item by the resulting Observable until the Observable * returned from {@code itemDelay} emits an item * @return an Observable that delays the subscription and emissions of the source Observable via another * Observable on a per-item basis * @see <a href="http://reactivex.io/documentation/operators/delay.html">ReactiveX operators documentation: Delay</a> */ public final <U, V> Observable<T> delay( Func0<? extends Observable<U>> subscriptionDelay, Func1<? super T, ? extends Observable<V>> itemDelay) { return delaySubscription(subscriptionDelay).lift(new OperatorDelayWithSelector<T, V>(this, itemDelay)); } /** * Returns an Observable that delays the emissions of the source Observable via another Observable on a * per-item basis. * <p> * <img width="640" height="450" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/delay.o.png" alt=""> * <p> * <em>Note:</em> the resulting Observable will immediately propagate any {@code onError} notification * from the source Observable. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code delay} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <U> * the item delay value type (ignored) * @param itemDelay * a function that returns an Observable for each item emitted by the source Observable, which is * then used to delay the emission of that item by the resulting Observable until the Observable * returned from {@code itemDelay} emits an item * @return an Observable that delays the emissions of the source Observable via another Observable on a * per-item basis * @see <a href="http://reactivex.io/documentation/operators/delay.html">ReactiveX operators documentation: Delay</a> */ public final <U> Observable<T> delay(Func1<? super T, ? extends Observable<U>> itemDelay) { return lift(new OperatorDelayWithSelector<T, U>(this, itemDelay)); } /** * Returns an Observable that emits the items emitted by the source Observable shifted forward in time by a * specified delay. Error notifications from the source Observable are not delayed. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/delay.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code delay} operates by default on the {@code compuation} {@link Scheduler}.</dd> * </dl> * * @param delay * the delay to shift the source by * @param unit * the {@link TimeUnit} in which {@code period} is defined * @return the source Observable shifted in time by the specified delay * @see <a href="http://reactivex.io/documentation/operators/delay.html">ReactiveX operators documentation: Delay</a> */ public final Observable<T> delay(long delay, TimeUnit unit) { return delay(delay, unit, Schedulers.computation()); } /** * Returns an Observable that emits the items emitted by the source Observable shifted forward in time by a * specified delay. Error notifications from the source Observable are not delayed. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/delay.s.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param delay * the delay to shift the source by * @param unit * the time unit of {@code delay} * @param scheduler * the {@link Scheduler} to use for delaying * @return the source Observable shifted in time by the specified delay * @see <a href="http://reactivex.io/documentation/operators/delay.html">ReactiveX operators documentation: Delay</a> */ public final Observable<T> delay(long delay, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorDelay<T>(this, delay, unit, scheduler)); } /** * Returns an Observable that delays the subscription to the source Observable by a given amount of time. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/delaySubscription.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code delay} operates by default on the {@code compuation} {@link Scheduler}.</dd> * </dl> * * @param delay * the time to delay the subscription * @param unit * the time unit of {@code delay} * @return an Observable that delays the subscription to the source Observable by the given amount * @see <a href="http://reactivex.io/documentation/operators/delay.html">ReactiveX operators documentation: Delay</a> */ public final Observable<T> delaySubscription(long delay, TimeUnit unit) { return delaySubscription(delay, unit, Schedulers.computation()); } /** * Returns an Observable that delays the subscription to the source Observable by a given amount of time, * both waiting and subscribing on a given Scheduler. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/delaySubscription.s.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param delay * the time to delay the subscription * @param unit * the time unit of {@code delay} * @param scheduler * the Scheduler on which the waiting and subscription will happen * @return an Observable that delays the subscription to the source Observable by a given * amount, waiting and subscribing on the given Scheduler * @see <a href="http://reactivex.io/documentation/operators/delay.html">ReactiveX operators documentation: Delay</a> */ public final Observable<T> delaySubscription(long delay, TimeUnit unit, Scheduler scheduler) { return create(new OnSubscribeDelaySubscription<T>(this, delay, unit, scheduler)); } /** * Returns an Observable that delays the subscription to the source Observable until a second Observable * emits an item. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/delaySubscription.o.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code delay} operates by default on the {@code compuation} {@link Scheduler}.</dd> * </dl> * * @param subscriptionDelay * a function that returns an Observable that triggers the subscription to the source Observable * once it emits any item * @return an Observable that delays the subscription to the source Observable until the Observable returned * by {@code subscriptionDelay} emits an item * @see <a href="http://reactivex.io/documentation/operators/delay.html">ReactiveX operators documentation: Delay</a> */ public final <U> Observable<T> delaySubscription(Func0<? extends Observable<U>> subscriptionDelay) { return create(new OnSubscribeDelaySubscriptionWithSelector<T, U>(this, subscriptionDelay)); } /** * Returns an Observable that reverses the effect of {@link #materialize materialize} by transforming the * {@link Notification} objects emitted by the source Observable into the items or notifications they * represent. * <p> * <img width="640" height="335" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/dematerialize.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code dematerialize} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits the items and notifications embedded in the {@link Notification} objects * emitted by the source Observable * @throws OnErrorNotImplementedException * if the source Observable is not of type {@code Observable<Notification<T>>} * @see <a href="http://reactivex.io/documentation/operators/materialize-dematerialize.html">ReactiveX operators documentation: Dematerialize</a> */ @SuppressWarnings({"unchecked"}) public final <T2> Observable<T2> dematerialize() { return lift(OperatorDematerialize.instance()); } /** * Returns an Observable that emits all items emitted by the source Observable that are distinct. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/distinct.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code distinct} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits only those items emitted by the source Observable that are distinct from * each other * @see <a href="http://reactivex.io/documentation/operators/distinct.html">ReactiveX operators documentation: Distinct</a> */ public final Observable<T> distinct() { return lift(new OperatorDistinct<T, T>(UtilityFunctions.<T>identity())); } /** * Returns an Observable that emits all items emitted by the source Observable that are distinct according * to a key selector function. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/distinct.key.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code distinct} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * a function that projects an emitted item to a key value that is used to decide whether an item * is distinct from another one or not * @return an Observable that emits those items emitted by the source Observable that have distinct keys * @see <a href="http://reactivex.io/documentation/operators/distinct.html">ReactiveX operators documentation: Distinct</a> */ public final <U> Observable<T> distinct(Func1<? super T, ? extends U> keySelector) { return lift(new OperatorDistinct<T, U>(keySelector)); } /** * Returns an Observable that emits all items emitted by the source Observable that are distinct from their * immediate predecessors. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/distinctUntilChanged.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code distinctUntilChanged} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits those items from the source Observable that are distinct from their * immediate predecessors * @see <a href="http://reactivex.io/documentation/operators/distinct.html">ReactiveX operators documentation: Distinct</a> */ public final Observable<T> distinctUntilChanged() { return lift(new OperatorDistinctUntilChanged<T, T>(UtilityFunctions.<T>identity())); } /** * Returns an Observable that emits all items emitted by the source Observable that are distinct from their * immediate predecessors, according to a key selector function. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/distinctUntilChanged.key.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code distinctUntilChanged} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * a function that projects an emitted item to a key value that is used to decide whether an item * is distinct from another one or not * @return an Observable that emits those items from the source Observable whose keys are distinct from * those of their immediate predecessors * @see <a href="http://reactivex.io/documentation/operators/distinct.html">ReactiveX operators documentation: Distinct</a> */ public final <U> Observable<T> distinctUntilChanged(Func1<? super T, ? extends U> keySelector) { return lift(new OperatorDistinctUntilChanged<T, U>(keySelector)); } /** * Modifies the source Observable so that it invokes an action when it calls {@code onCompleted}. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/doOnCompleted.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnCompleted} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onCompleted * the action to invoke when the source Observable calls {@code onCompleted} * @return the source Observable with the side-effecting behavior applied * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> */ public final Observable<T> doOnCompleted(final Action0 onCompleted) { Observer<T> observer = new Observer<T>() { @Override public final void onCompleted() { onCompleted.call(); } @Override public final void onError(Throwable e) { } @Override public final void onNext(T args) { } }; return lift(new OperatorDoOnEach<T>(observer)); } /** * Modifies the source Observable so that it invokes an action for each item it emits. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/doOnEach.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnEach} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onNotification * the action to invoke for each item emitted by the source Observable * @return the source Observable with the side-effecting behavior applied * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> */ public final Observable<T> doOnEach(final Action1<Notification<? super T>> onNotification) { Observer<T> observer = new Observer<T>() { @Override public final void onCompleted() { onNotification.call(Notification.createOnCompleted()); } @Override public final void onError(Throwable e) { onNotification.call(Notification.createOnError(e)); } @Override public final void onNext(T v) { onNotification.call(Notification.createOnNext(v)); } }; return lift(new OperatorDoOnEach<T>(observer)); } /** * Modifies the source Observable so that it notifies an Observer for each item it emits. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/doOnEach.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnEach} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param observer * the action to invoke for each item emitted by the source Observable * @return the source Observable with the side-effecting behavior applied * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> */ public final Observable<T> doOnEach(Observer<? super T> observer) { return lift(new OperatorDoOnEach<T>(observer)); } /** * Modifies the source Observable so that it invokes an action if it calls {@code onError}. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/doOnError.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnError} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onError * the action to invoke if the source Observable calls {@code onError} * @return the source Observable with the side-effecting behavior applied * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> */ public final Observable<T> doOnError(final Action1<Throwable> onError) { Observer<T> observer = new Observer<T>() { @Override public final void onCompleted() { } @Override public final void onError(Throwable e) { onError.call(e); } @Override public final void onNext(T args) { } }; return lift(new OperatorDoOnEach<T>(observer)); } /** * Modifies the source Observable so that it invokes an action when it calls {@code onNext}. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/doOnNext.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnNext} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onNext * the action to invoke when the source Observable calls {@code onNext} * @return the source Observable with the side-effecting behavior applied * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> */ public final Observable<T> doOnNext(final Action1<? super T> onNext) { Observer<T> observer = new Observer<T>() { @Override public final void onCompleted() { } @Override public final void onError(Throwable e) { } @Override public final void onNext(T args) { onNext.call(args); } }; return lift(new OperatorDoOnEach<T>(observer)); } /** * Modifies the source {@code Observable} so that it invokes the given action when it receives a request for * more items. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnRequest} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onRequest * the action that gets called when an observer requests items from this {@code Observable} * @return the source {@code Observable} modified so as to call this Action when appropriate * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Beta public final Observable<T> doOnRequest(final Action1<Long> onRequest) { return lift(new OperatorDoOnRequest<T>(onRequest)); } /** * Modifies the source {@code Observable} so that it invokes the given action when it is subscribed from * its subscribers. Each subscription will result in an invocation of the given action except when the * source {@code Observable} is reference counted, in which case the source {@code Observable} will invoke * the given action for the first subscription. * <p> * <img width="640" height="390" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/doOnSubscribe.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnSubscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param subscribe * the action that gets called when an observer subscribes to this {@code Observable} * @return the source {@code Observable} modified so as to call this Action when appropriate * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> */ public final Observable<T> doOnSubscribe(final Action0 subscribe) { return lift(new OperatorDoOnSubscribe<T>(subscribe)); } /** * Modifies the source Observable so that it invokes an action when it calls {@code onCompleted} or * {@code onError}. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/doOnTerminate.png" alt=""> * <p> * This differs from {@code finallyDo} in that this happens <em>before</em> the {@code onCompleted} or * {@code onError} notification. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnTerminate} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onTerminate * the action to invoke when the source Observable calls {@code onCompleted} or {@code onError} * @return the source Observable with the side-effecting behavior applied * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> * @see #finallyDo(Action0) */ public final Observable<T> doOnTerminate(final Action0 onTerminate) { Observer<T> observer = new Observer<T>() { @Override public final void onCompleted() { onTerminate.call(); } @Override public final void onError(Throwable e) { onTerminate.call(); } @Override public final void onNext(T args) { } }; return lift(new OperatorDoOnEach<T>(observer)); } /** * Modifies the source {@code Observable} so that it invokes the given action when it is unsubscribed from * its subscribers. Each un-subscription will result in an invocation of the given action except when the * source {@code Observable} is reference counted, in which case the source {@code Observable} will invoke * the given action for the very last un-subscription. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/doOnUnsubscribe.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code doOnUnsubscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param unsubscribe * the action that gets called when this {@code Observable} is unsubscribed * @return the source {@code Observable} modified so as to call this Action when appropriate * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> */ public final Observable<T> doOnUnsubscribe(final Action0 unsubscribe) { return lift(new OperatorDoOnUnsubscribe<T>(unsubscribe)); } /** * Returns an Observable that emits the single item at a specified index in a sequence of emissions from a * source Observbable. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/elementAt.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code elementAt} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param index * the zero-based index of the item to retrieve * @return an Observable that emits a single item: the item at the specified position in the sequence of * those emitted by the source Observable * @throws IndexOutOfBoundsException * if {@code index} is greater than or equal to the number of items emitted by the source * Observable, or * if {@code index} is less than 0 * @see <a href="http://reactivex.io/documentation/operators/elementat.html">ReactiveX operators documentation: ElementAt</a> */ public final Observable<T> elementAt(int index) { return lift(new OperatorElementAt<T>(index)); } /** * Returns an Observable that emits the item found at a specified index in a sequence of emissions from a * source Observable, or a default item if that index is out of range. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/elementAtOrDefault.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code elementAtOrDefault} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param index * the zero-based index of the item to retrieve * @param defaultValue * the default item * @return an Observable that emits the item at the specified position in the sequence emitted by the source * Observable, or the default item if that index is outside the bounds of the source sequence * @throws IndexOutOfBoundsException * if {@code index} is less than 0 * @see <a href="http://reactivex.io/documentation/operators/elementat.html">ReactiveX operators documentation: ElementAt</a> */ public final Observable<T> elementAtOrDefault(int index, T defaultValue) { return lift(new OperatorElementAt<T>(index, defaultValue)); } /** * Returns an Observable that emits {@code true} if any item emitted by the source Observable satisfies a * specified condition, otherwise {@code false}. <em>Note:</em> this always emits {@code false} if the * source Observable is empty. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/exists.png" alt=""> * <p> * In Rx.Net this is the {@code any} Observer but we renamed it in RxJava to better match Java naming * idioms. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code exists} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * the condition to test items emitted by the source Observable * @return an Observable that emits a Boolean that indicates whether any item emitted by the source * Observable satisfies the {@code predicate} * @see <a href="http://reactivex.io/documentation/operators/contains.html">ReactiveX operators documentation: Contains</a> */ public final Observable<Boolean> exists(Func1<? super T, Boolean> predicate) { return lift(new OperatorAny<T>(predicate, false)); } /** * Filters items emitted by an Observable by only emitting those that satisfy a specified predicate. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/filter.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code filter} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * a function that evaluates each item emitted by the source Observable, returning {@code true} * if it passes the filter * @return an Observable that emits only those items emitted by the source Observable that the filter * evaluates as {@code true} * @see <a href="http://reactivex.io/documentation/operators/filter.html">ReactiveX operators documentation: Filter</a> */ public final Observable<T> filter(Func1<? super T, Boolean> predicate) { return lift(new OperatorFilter<T>(predicate)); } /** * Registers an {@link Action0} to be called when this Observable invokes either * {@link Observer#onCompleted onCompleted} or {@link Observer#onError onError}. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/finallyDo.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code finallyDo} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param action * an {@link Action0} to be invoked when the source Observable finishes * @return an Observable that emits the same items as the source Observable, then invokes the * {@link Action0} * @see <a href="http://reactivex.io/documentation/operators/do.html">ReactiveX operators documentation: Do</a> * @see #doOnTerminate(Action0) */ public final Observable<T> finallyDo(Action0 action) { return lift(new OperatorFinally<T>(action)); } /** * Returns an Observable that emits only the very first item emitted by the source Observable, or notifies * of an {@code NoSuchElementException} if the source Observable is empty. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/first.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code first} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits only the very first item emitted by the source Observable, or raises an * {@code NoSuchElementException} if the source Observable is empty * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> first() { return take(1).single(); } /** * Returns an Observable that emits only the very first item emitted by the source Observable that satisfies * a specified condition, or notifies of an {@code NoSuchElementException} if no such items are emitted. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/firstN.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code first} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * the condition that an item emitted by the source Observable has to satisfy * @return an Observable that emits only the very first item emitted by the source Observable that satisfies * the {@code predicate}, or raises an {@code NoSuchElementException} if no such items are emitted * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> first(Func1<? super T, Boolean> predicate) { return takeFirst(predicate).single(); } /** * Returns an Observable that emits only the very first item emitted by the source Observable, or a default * item if the source Observable completes without emitting anything. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/firstOrDefault.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code firstOrDefault} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param defaultValue * the default item to emit if the source Observable doesn't emit anything * @return an Observable that emits only the very first item from the source, or a default item if the * source Observable completes without emitting any items * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> firstOrDefault(T defaultValue) { return take(1).singleOrDefault(defaultValue); } /** * Returns an Observable that emits only the very first item emitted by the source Observable that satisfies * a specified condition, or a default item if the source Observable emits no such items. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/firstOrDefaultN.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code firstOrDefault} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * the condition any item emitted by the source Observable has to satisfy * @param defaultValue * the default item to emit if the source Observable doesn't emit anything that satisfies the * {@code predicate} * @return an Observable that emits only the very first item emitted by the source Observable that satisfies * the {@code predicate}, or a default item if the source Observable emits no such items * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> firstOrDefault(T defaultValue, Func1<? super T, Boolean> predicate) { return takeFirst(predicate).singleOrDefault(defaultValue); } /** * Returns an Observable that emits items based on applying a function that you supply to each item emitted * by the source Observable, where that function returns an Observable, and then merging those resulting * Observables and emitting the results of this merger. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/flatMap.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code flatMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param func * a function that, when applied to an item emitted by the source Observable, returns an * Observable * @return an Observable that emits the result of applying the transformation function to each item emitted * by the source Observable and merging the results of the Observables obtained from this * transformation * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> */ public final <R> Observable<R> flatMap(Func1<? super T, ? extends Observable<? extends R>> func) { return merge(map(func)); } /** * Returns an Observable that emits items based on applying a function that you supply to each item emitted * by the source Observable, where that function returns an Observable, and then merging those resulting * Observables and emitting the results of this merger, while limiting the maximum number of concurrent * subscriptions to these Observables. * <p> * <!-- <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/flatMap.png" alt=""> --> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code flatMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param func * a function that, when applied to an item emitted by the source Observable, returns an * Observable * @param maxConcurrent * the maximum number of Observables that may be subscribed to concurrently * @return an Observable that emits the result of applying the transformation function to each item emitted * by the source Observable and merging the results of the Observables obtained from this * transformation * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Beta public final <R> Observable<R> flatMap(Func1<? super T, ? extends Observable<? extends R>> func, int maxConcurrent) { return merge(map(func), maxConcurrent); } /** * Returns an Observable that applies a function to each item emitted or notification raised by the source * Observable and then flattens the Observables returned from these functions and emits the resulting items. * <p> * <img width="640" height="410" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeMap.nce.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code flatMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <R> * the result type * @param onNext * a function that returns an Observable to merge for each item emitted by the source Observable * @param onError * a function that returns an Observable to merge for an onError notification from the source * Observable * @param onCompleted * a function that returns an Observable to merge for an onCompleted notification from the source * Observable * @return an Observable that emits the results of merging the Observables returned from applying the * specified functions to the emissions and notifications of the source Observable * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> */ public final <R> Observable<R> flatMap( Func1<? super T, ? extends Observable<? extends R>> onNext, Func1<? super Throwable, ? extends Observable<? extends R>> onError, Func0<? extends Observable<? extends R>> onCompleted) { return merge(mapNotification(onNext, onError, onCompleted)); } /** * Returns an Observable that applies a function to each item emitted or notification raised by the source * Observable and then flattens the Observables returned from these functions and emits the resulting items, * while limiting the maximum number of concurrent subscriptions to these Observables. * <p> * <!-- <img width="640" height="410" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeMap.nce.png" alt=""> --> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code flatMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <R> * the result type * @param onNext * a function that returns an Observable to merge for each item emitted by the source Observable * @param onError * a function that returns an Observable to merge for an onError notification from the source * Observable * @param onCompleted * a function that returns an Observable to merge for an onCompleted notification from the source * Observable * @param maxConcurrent * the maximum number of Observables that may be subscribed to concurrently * @return an Observable that emits the results of merging the Observables returned from applying the * specified functions to the emissions and notifications of the source Observable * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Beta public final <R> Observable<R> flatMap( Func1<? super T, ? extends Observable<? extends R>> onNext, Func1<? super Throwable, ? extends Observable<? extends R>> onError, Func0<? extends Observable<? extends R>> onCompleted, int maxConcurrent) { return merge(mapNotification(onNext, onError, onCompleted), maxConcurrent); } /** * Returns an Observable that emits the results of a specified function to the pair of values emitted by the * source Observable and a specified collection Observable. * <p> * <img width="640" height="390" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeMap.r.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code flatMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <U> * the type of items emitted by the collection Observable * @param <R> * the type of items emitted by the resulting Observable * @param collectionSelector * a function that returns an Observable for each item emitted by the source Observable * @param resultSelector * a function that combines one item emitted by each of the source and collection Observables and * returns an item to be emitted by the resulting Observable * @return an Observable that emits the results of applying a function to a pair of values emitted by the * source Observable and the collection Observable * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> */ public final <U, R> Observable<R> flatMap(final Func1<? super T, ? extends Observable<? extends U>> collectionSelector, final Func2<? super T, ? super U, ? extends R> resultSelector) { return merge(lift(new OperatorMapPair<T, U, R>(collectionSelector, resultSelector))); } /** * Returns an Observable that emits the results of a specified function to the pair of values emitted by the * source Observable and a specified collection Observable, while limiting the maximum number of concurrent * subscriptions to these Observables. * <p> * <!-- <img width="640" height="390" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeMap.r.png" alt=""> --> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code flatMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <U> * the type of items emitted by the collection Observable * @param <R> * the type of items emitted by the resulting Observable * @param collectionSelector * a function that returns an Observable for each item emitted by the source Observable * @param resultSelector * a function that combines one item emitted by each of the source and collection Observables and * returns an item to be emitted by the resulting Observable * @param maxConcurrent * the maximum number of Observables that may be subscribed to concurrently * @return an Observable that emits the results of applying a function to a pair of values emitted by the * source Observable and the collection Observable * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Beta public final <U, R> Observable<R> flatMap(final Func1<? super T, ? extends Observable<? extends U>> collectionSelector, final Func2<? super T, ? super U, ? extends R> resultSelector, int maxConcurrent) { return merge(lift(new OperatorMapPair<T, U, R>(collectionSelector, resultSelector)), maxConcurrent); } /** * Returns an Observable that merges each item emitted by the source Observable with the values in an * Iterable corresponding to that item that is generated by a selector. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeMapIterable.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code flatMapIterable} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <R> * the type of item emitted by the resulting Observable * @param collectionSelector * a function that returns an Iterable sequence of values for when given an item emitted by the * source Observable * @return an Observable that emits the results of merging the items emitted by the source Observable with * the values in the Iterables corresponding to those items, as generated by {@code collectionSelector} * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> */ public final <R> Observable<R> flatMapIterable(Func1<? super T, ? extends Iterable<? extends R>> collectionSelector) { return merge(map(OperatorMapPair.convertSelector(collectionSelector))); } /** * Returns an Observable that emits the results of applying a function to the pair of values from the source * Observable and an Iterable corresponding to that item that is generated by a selector. * <p> * <img width="640" height="390" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/mergeMapIterable.r.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code flatMapIterable} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <U> * the collection element type * @param <R> * the type of item emited by the resulting Observable * @param collectionSelector * a function that returns an Iterable sequence of values for each item emitted by the source * Observable * @param resultSelector * a function that returns an item based on the item emitted by the source Observable and the * Iterable returned for that item by the {@code collectionSelector} * @return an Observable that emits the items returned by {@code resultSelector} for each item in the source * Observable * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> */ public final <U, R> Observable<R> flatMapIterable(Func1<? super T, ? extends Iterable<? extends U>> collectionSelector, Func2<? super T, ? super U, ? extends R> resultSelector) { return flatMap(OperatorMapPair.convertSelector(collectionSelector), resultSelector); } /** * Subscribes to the {@link Observable} and receives notifications for each element. * <p> * Alias to {@link #subscribe(Action1)} * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code forEach} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onNext * {@link Action1} to execute for each item. * @throws IllegalArgumentException * if {@code onNext} is null, or * if {@code onError} is null, or * if {@code onComplete} is null * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> */ public final void forEach(final Action1<? super T> onNext) { subscribe(onNext); } /** * Subscribes to the {@link Observable} and receives notifications for each element and error events. * <p> * Alias to {@link #subscribe(Action1, Action1)} * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code forEach} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onNext * {@link Action1} to execute for each item. * @param onError * {@link Action1} to execute when an error is emitted. * @throws IllegalArgumentException * if {@code onNext} is null, or * if {@code onError} is null, or * if {@code onComplete} is null * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> */ public final void forEach(final Action1<? super T> onNext, final Action1<Throwable> onError) { subscribe(onNext, onError); } /** * Subscribes to the {@link Observable} and receives notifications for each element and the terminal events. * <p> * Alias to {@link #subscribe(Action1, Action1, Action0)} * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code forEach} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onNext * {@link Action1} to execute for each item. * @param onError * {@link Action1} to execute when an error is emitted. * @param onComplete * {@link Action0} to execute when completion is signalled. * @throws IllegalArgumentException * if {@code onNext} is null, or * if {@code onError} is null, or * if {@code onComplete} is null * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> */ public final void forEach(final Action1<? super T> onNext, final Action1<Throwable> onError, final Action0 onComplete) { subscribe(onNext, onError, onComplete); } /** * Groups the items emitted by an {@code Observable} according to a specified criterion, and emits these * grouped items as {@link GroupedObservable}s, one {@code GroupedObservable} per group. * <p> * <img width="640" height="360" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/groupBy.png" alt=""> * <p> * <em>Note:</em> A {@link GroupedObservable} will cache the items it is to emit until such time as it * is subscribed to. For this reason, in order to avoid memory leaks, you should not simply ignore those * {@code GroupedObservable}s that do not concern you. Instead, you can signal to them that they may * discard their buffers by applying an operator like {@link #take}{@code (0)} to them. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code groupBy} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * a function that extracts the key for each item * @param elementSelector * a function that extracts the return element for each item * @param <K> * the key type * @param <R> * the element type * @return an {@code Observable} that emits {@link GroupedObservable}s, each of which corresponds to a * unique key value and each of which emits those items from the source Observable that share that * key value * @see <a href="http://reactivex.io/documentation/operators/groupby.html">ReactiveX operators documentation: GroupBy</a> */ public final <K, R> Observable<GroupedObservable<K, R>> groupBy(final Func1<? super T, ? extends K> keySelector, final Func1<? super T, ? extends R> elementSelector) { return lift(new OperatorGroupBy<T, K, R>(keySelector, elementSelector)); } /** * Groups the items emitted by an {@code Observable} according to a specified criterion, and emits these * grouped items as {@link GroupedObservable}s, one {@code GroupedObservable} per group. * <p> * <img width="640" height="360" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/groupBy.png" alt=""> * <p> * <em>Note:</em> A {@link GroupedObservable} will cache the items it is to emit until such time as it * is subscribed to. For this reason, in order to avoid memory leaks, you should not simply ignore those * {@code GroupedObservable}s that do not concern you. Instead, you can signal to them that they may * discard their buffers by applying an operator like {@link #take}{@code (0)} to them. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code groupBy} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * a function that extracts the key for each item * @param <K> * the key type * @return an {@code Observable} that emits {@link GroupedObservable}s, each of which corresponds to a * unique key value and each of which emits those items from the source Observable that share that * key value * @see <a href="http://reactivex.io/documentation/operators/groupby.html">ReactiveX operators documentation: GroupBy</a> */ public final <K> Observable<GroupedObservable<K, T>> groupBy(final Func1<? super T, ? extends K> keySelector) { return lift(new OperatorGroupBy<T, K, T>(keySelector)); } /** * Returns an Observable that correlates two Observables when they overlap in time and groups the results. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/groupJoin.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code groupJoin} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param right * the other Observable to correlate items from the source Observable with * @param leftDuration * a function that returns an Observable whose emissions indicate the duration of the values of * the source Observable * @param rightDuration * a function that returns an Observable whose emissions indicate the duration of the values of * the {@code right} Observable * @param resultSelector * a function that takes an item emitted by each Observable and returns the value to be emitted * by the resulting Observable * @return an Observable that emits items based on combining those items emitted by the source Observables * whose durations overlap * @see <a href="http://reactivex.io/documentation/operators/join.html">ReactiveX operators documentation: Join</a> */ public final <T2, D1, D2, R> Observable<R> groupJoin(Observable<T2> right, Func1<? super T, ? extends Observable<D1>> leftDuration, Func1<? super T2, ? extends Observable<D2>> rightDuration, Func2<? super T, ? super Observable<T2>, ? extends R> resultSelector) { return create(new OnSubscribeGroupJoin<T, T2, D1, D2, R>(this, right, leftDuration, rightDuration, resultSelector)); } /** * Ignores all items emitted by the source Observable and only calls {@code onCompleted} or {@code onError}. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/ignoreElements.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code ignoreElements} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an empty Observable that only calls {@code onCompleted} or {@code onError}, based on which one is * called by the source Observable * @see <a href="http://reactivex.io/documentation/operators/ignoreelements.html">ReactiveX operators documentation: IgnoreElements</a> */ public final Observable<T> ignoreElements() { return filter(UtilityFunctions.alwaysFalse()); } /** * Returns an Observable that emits {@code true} if the source Observable is empty, otherwise {@code false}. * <p> * In Rx.Net this is negated as the {@code any} Observer but we renamed this in RxJava to better match Java * naming idioms. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/isEmpty.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code isEmpty} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits a Boolean * @see <a href="http://reactivex.io/documentation/operators/contains.html">ReactiveX operators documentation: Contains</a> */ public final Observable<Boolean> isEmpty() { return lift(new OperatorAny<T>(UtilityFunctions.alwaysTrue(), true)); } /** * Correlates the items emitted by two Observables based on overlapping durations. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/join_.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code join} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param right * the second Observable to join items from * @param leftDurationSelector * a function to select a duration for each item emitted by the source Observable, used to * determine overlap * @param rightDurationSelector * a function to select a duration for each item emitted by the {@code right} Observable, used to * determine overlap * @param resultSelector * a function that computes an item to be emitted by the resulting Observable for any two * overlapping items emitted by the two Observables * @return an Observable that emits items correlating to items emitted by the source Observables that have * overlapping durations * @see <a href="http://reactivex.io/documentation/operators/join.html">ReactiveX operators documentation: Join</a> */ public final <TRight, TLeftDuration, TRightDuration, R> Observable<R> join(Observable<TRight> right, Func1<T, Observable<TLeftDuration>> leftDurationSelector, Func1<TRight, Observable<TRightDuration>> rightDurationSelector, Func2<T, TRight, R> resultSelector) { return create(new OnSubscribeJoin<T, TRight, TLeftDuration, TRightDuration, R>(this, right, leftDurationSelector, rightDurationSelector, resultSelector)); } /** * Returns an Observable that emits the last item emitted by the source Observable or notifies observers of * a {@code NoSuchElementException} if the source Observable is empty. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/last.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code last} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits the last item from the source Observable or notifies observers of an * error * @see <a href="http://reactivex.io/documentation/operators/last.html">ReactiveX operators documentation: Last</a> */ public final Observable<T> last() { return takeLast(1).single(); } /** * Returns an Observable that emits only the last item emitted by the source Observable that satisfies a * given condition, or notifies of a {@code NoSuchElementException} if no such items are emitted. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/last.p.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code last} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * the condition any source emitted item has to satisfy * @return an Observable that emits only the last item satisfying the given condition from the source, or an * {@code NoSuchElementException} if no such items are emitted * @throws IllegalArgumentException * if no items that match the predicate are emitted by the source Observable * @see <a href="http://reactivex.io/documentation/operators/last.html">ReactiveX operators documentation: Last</a> */ public final Observable<T> last(Func1<? super T, Boolean> predicate) { return filter(predicate).takeLast(1).single(); } /** * Returns an Observable that emits only the last item emitted by the source Observable, or a default item * if the source Observable completes without emitting any items. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/lastOrDefault.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code lastOrDefault} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param defaultValue * the default item to emit if the source Observable is empty * @return an Observable that emits only the last item emitted by the source Observable, or a default item * if the source Observable is empty * @see <a href="http://reactivex.io/documentation/operators/last.html">ReactiveX operators documentation: Last</a> */ public final Observable<T> lastOrDefault(T defaultValue) { return takeLast(1).singleOrDefault(defaultValue); } /** * Returns an Observable that emits only the last item emitted by the source Observable that satisfies a * specified condition, or a default item if no such item is emitted by the source Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/lastOrDefault.p.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code lastOrDefault} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param defaultValue * the default item to emit if the source Observable doesn't emit anything that satisfies the * specified {@code predicate} * @param predicate * the condition any item emitted by the source Observable has to satisfy * @return an Observable that emits only the last item emitted by the source Observable that satisfies the * given condition, or a default item if no such item is emitted by the source Observable * @see <a href="http://reactivex.io/documentation/operators/last.html">ReactiveX operators documentation: Last</a> */ public final Observable<T> lastOrDefault(T defaultValue, Func1<? super T, Boolean> predicate) { return filter(predicate).takeLast(1).singleOrDefault(defaultValue); } /** * Returns an Observable that emits only the first {@code num} items emitted by the source Observable. * <p> * Alias of {@link #take(int)} to match Java 8 Stream API naming convention. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/take.png" alt=""> * <p> * This method returns an Observable that will invoke a subscribing {@link Observer}'s * {@link Observer#onNext onNext} function a maximum of {@code num} times before invoking * {@link Observer#onCompleted onCompleted}. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code limit} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param num * the maximum number of items to emit * @return an Observable that emits only the first {@code num} items emitted by the source Observable, or * all of the items from the source Observable if that Observable emits fewer than {@code num} items * @see <a href="http://reactivex.io/documentation/operators/take.html">ReactiveX operators documentation: Take</a> */ public final Observable<T> limit(int num) { return take(num); } /** * Returns an Observable that applies a specified function to each item emitted by the source Observable and * emits the results of these function applications. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/map.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code map} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param func * a function to apply to each item emitted by the Observable * @return an Observable that emits the items from the source Observable, transformed by the specified * function * @see <a href="http://reactivex.io/documentation/operators/map.html">ReactiveX operators documentation: Map</a> */ public final <R> Observable<R> map(Func1<? super T, ? extends R> func) { return lift(new OperatorMap<T, R>(func)); } private final <R> Observable<R> mapNotification(Func1<? super T, ? extends R> onNext, Func1<? super Throwable, ? extends R> onError, Func0<? extends R> onCompleted) { return lift(new OperatorMapNotification<T, R>(onNext, onError, onCompleted)); } /** * Returns an Observable that represents all of the emissions <em>and</em> notifications from the source * Observable into emissions marked with their original types within {@link Notification} objects. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/materialize.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code materialize} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits items that are the result of materializing the items and notifications * of the source Observable * @see <a href="http://reactivex.io/documentation/operators/materialize-dematerialize.html">ReactiveX operators documentation: Materialize</a> */ public final Observable<Notification<T>> materialize() { return lift(OperatorMaterialize.<T>instance()); } /** * Flattens this and another Observable into a single Observable, without any transformation. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/merge.png" alt=""> * <p> * You can combine items emitted by multiple Observables so that they appear as a single Observable, by * using the {@code mergeWith} method. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code mergeWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * an Observable to be merged * @return an Observable that emits all of the items emitted by the source Observables * @see <a href="http://reactivex.io/documentation/operators/merge.html">ReactiveX operators documentation: Merge</a> */ public final Observable<T> mergeWith(Observable<? extends T> t1) { return merge(this, t1); } /** * Modifies an Observable to perform its emissions and notifications on a specified {@link Scheduler}, * asynchronously with an unbounded buffer. * <p> * <img width="640" height="308" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/observeOn.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param scheduler * the {@link Scheduler} to notify {@link Observer}s on * @return the source Observable modified so that its {@link Observer}s are notified on the specified * {@link Scheduler} * @see <a href="http://reactivex.io/documentation/operators/observeon.html">ReactiveX operators documentation: ObserveOn</a> * @see <a href="http://www.grahamlea.com/2014/07/rxjava-threading-examples/">RxJava Threading Examples</a> * @see #subscribeOn */ public final Observable<T> observeOn(Scheduler scheduler) { if (this instanceof ScalarSynchronousObservable) { return ((ScalarSynchronousObservable<T>)this).scalarScheduleOn(scheduler); } return lift(new OperatorObserveOn<T>(scheduler)); } /** * Filters the items emitted by an Observable, only emitting those of the specified type. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/ofClass.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code ofType} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param klass * the class type to filter the items emitted by the source Observable * @return an Observable that emits items from the source Observable of type {@code klass} * @see <a href="http://reactivex.io/documentation/operators/filter.html">ReactiveX operators documentation: Filter</a> */ public final <R> Observable<R> ofType(final Class<R> klass) { return filter(new Func1<T, Boolean>() { @Override public final Boolean call(T t) { return klass.isInstance(t); } }).cast(klass); } /** * Instructs an Observable that is emitting items faster than its observer can consume them to buffer these * items indefinitely until they can be emitted. * <p> * <img width="640" height="300" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/bp.obp.buffer.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onBackpressureBuffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return the source Observable modified to buffer items to the extent system resources allow * @see <a href="http://reactivex.io/documentation/operators/backpressure.html">ReactiveX operators documentation: backpressure operators</a> */ public final Observable<T> onBackpressureBuffer() { return lift(new OperatorOnBackpressureBuffer<T>()); } /** * Instructs an Observable that is emitting items faster than its observer can consume them to buffer up to * a given amount of items until they can be emitted. The resulting Observable will {@code onError} emitting * a {@code BufferOverflowException} as soon as the buffer's capacity is exceeded, dropping all undelivered * items, and unsubscribing from the source. * <p> * <img width="640" height="300" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/bp.obp.buffer.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onBackpressureBuffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return the source Observable modified to buffer items up to the given capacity * @see <a href="http://reactivex.io/documentation/operators/backpressure.html">ReactiveX operators documentation: backpressure operators</a> * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Beta public final Observable<T> onBackpressureBuffer(long capacity) { return lift(new OperatorOnBackpressureBuffer<T>(capacity)); } /** * Instructs an Observable that is emitting items faster than its observer can consume them to buffer up to * a given amount of items until they can be emitted. The resulting Observable will {@code onError} emitting * a {@code BufferOverflowException} as soon as the buffer's capacity is exceeded, dropping all undelivered * items, unsubscribing from the source, and notifying the producer with {@code onOverflow}. * <p> * <img width="640" height="300" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/bp.obp.buffer.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onBackpressureBuffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return the source Observable modified to buffer items up to the given capacity * @see <a href="http://reactivex.io/documentation/operators/backpressure.html">ReactiveX operators documentation: backpressure operators</a> * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Beta public final Observable<T> onBackpressureBuffer(long capacity, Action0 onOverflow) { return lift(new OperatorOnBackpressureBuffer<T>(capacity, onOverflow)); } /** * Instructs an Observable that is emitting items faster than its observer can consume them to discard, * rather than emit, those items that its observer is not prepared to observe. * <p> * <img width="640" height="245" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/bp.obp.drop.png" alt=""> * <p> * If the downstream request count hits 0 then the Observable will refrain from calling {@code onNext} until * the observer invokes {@code request(n)} again to increase the request count. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onBackpressureDrop} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onDrop the action to invoke for each item dropped. onDrop action should be fast and should never block. * @return the source Observable modified to drop {@code onNext} notifications on overflow * @see <a href="http://reactivex.io/documentation/operators/backpressure.html">ReactiveX operators documentation: backpressure operators</a> * @Experimental The behavior of this can change at any time. * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Experimental public final Observable<T> onBackpressureDrop(Action1<? super T> onDrop) { return lift(new OperatorOnBackpressureDrop<T>(onDrop)); } /** * Instructs an Observable that is emitting items faster than its observer can consume them to discard, * rather than emit, those items that its observer is not prepared to observe. * <p> * <img width="640" height="245" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/bp.obp.drop.png" alt=""> * <p> * If the downstream request count hits 0 then the Observable will refrain from calling {@code onNext} until * the observer invokes {@code request(n)} again to increase the request count. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onBackpressureDrop} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return the source Observable modified to drop {@code onNext} notifications on overflow * @see <a href="http://reactivex.io/documentation/operators/backpressure.html">ReactiveX operators documentation: backpressure operators</a> */ public final Observable<T> onBackpressureDrop() { return lift(OperatorOnBackpressureDrop.<T>instance()); } /** * Instructs an Observable that is emitting items faster than its observer can consume them to * block the producer thread. * <p> * <img width="640" height="245" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/bp.obp.block.png" alt=""> * <p> * The producer side can emit up to {@code maxQueueLength} onNext elements without blocking, but the * consumer side considers the amount its downstream requested through {@code Producer.request(n)} * and doesn't emit more than requested even if more is available. For example, using * {@code onBackpressureBlock(384).observeOn(Schedulers.io())} will not throw a MissingBackpressureException. * <p> * Note that if the upstream Observable does support backpressure, this operator ignores that capability * and doesn't propagate any backpressure requests from downstream. * * @param maxQueueLength the maximum number of items the producer can emit without blocking * @return the source Observable modified to block {@code onNext} notifications on overflow * @see <a href="http://reactivex.io/documentation/operators/backpressure.html">ReactiveX operators documentation: backpressure operators</a> * @Experimental The behavior of this can change at any time. * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Experimental public final Observable<T> onBackpressureBlock(int maxQueueLength) { return lift(new OperatorOnBackpressureBlock<T>(maxQueueLength)); } /** * Instructs an Observable that is emitting items faster than its observer can consume them to block the * producer thread if the number of undelivered onNext events reaches the system-wide ring buffer size. * <p> * <img width="640" height="245" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/bp.obp.block.png" alt=""> * <p> * The producer side can emit up to the system-wide ring buffer size onNext elements without blocking, but * the consumer side considers the amount its downstream requested through {@code Producer.request(n)} * and doesn't emit more than requested even if available. * <p> * Note that if the upstream Observable does support backpressure, this operator ignores that capability * and doesn't propagate any backpressure requests from downstream. * * @return the source Observable modified to block {@code onNext} notifications on overflow * @see <a href="http://reactivex.io/documentation/operators/backpressure.html">ReactiveX operators documentation: backpressure operators</a> * @Experimental The behavior of this can change at any time. * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Experimental public final Observable<T> onBackpressureBlock() { return onBackpressureBlock(rx.internal.util.RxRingBuffer.SIZE); } /** * Instructs an Observable to pass control to another Observable rather than invoking * {@link Observer#onError onError} if it encounters an error. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/onErrorResumeNext.png" alt=""> * <p> * By default, when an Observable encounters an error that prevents it from emitting the expected item to * its {@link Observer}, the Observable invokes its Observer's {@code onError} method, and then quits * without invoking any more of its Observer's methods. The {@code onErrorResumeNext} method changes this * behavior. If you pass a function that returns an Observable ({@code resumeFunction}) to * {@code onErrorResumeNext}, if the original Observable encounters an error, instead of invoking its * Observer's {@code onError} method, it will instead relinquish control to the Observable returned from * {@code resumeFunction}, which will invoke the Observer's {@link Observer#onNext onNext} method if it is * able to do so. In such a case, because no Observable necessarily invokes {@code onError}, the Observer * may never know that an error happened. * <p> * You can use this to prevent errors from propagating or to supply fallback data should errors be * encountered. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onErrorResumeNext} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param resumeFunction * a function that returns an Observable that will take over if the source Observable encounters * an error * @return the original Observable, with appropriately modified behavior * @see <a href="http://reactivex.io/documentation/operators/catch.html">ReactiveX operators documentation: Catch</a> */ public final Observable<T> onErrorResumeNext(final Func1<Throwable, ? extends Observable<? extends T>> resumeFunction) { return lift(new OperatorOnErrorResumeNextViaFunction<T>(resumeFunction)); } /** * Instructs an Observable to pass control to another Observable rather than invoking * {@link Observer#onError onError} if it encounters an error. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/onErrorResumeNext.png" alt=""> * <p> * By default, when an Observable encounters an error that prevents it from emitting the expected item to * its {@link Observer}, the Observable invokes its Observer's {@code onError} method, and then quits * without invoking any more of its Observer's methods. The {@code onErrorResumeNext} method changes this * behavior. If you pass another Observable ({@code resumeSequence}) to an Observable's * {@code onErrorResumeNext} method, if the original Observable encounters an error, instead of invoking its * Observer's {@code onError} method, it will instead relinquish control to {@code resumeSequence} which * will invoke the Observer's {@link Observer#onNext onNext} method if it is able to do so. In such a case, * because no Observable necessarily invokes {@code onError}, the Observer may never know that an error * happened. * <p> * You can use this to prevent errors from propagating or to supply fallback data should errors be * encountered. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onErrorResumeNext} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param resumeSequence * a function that returns an Observable that will take over if the source Observable encounters * an error * @return the original Observable, with appropriately modified behavior * @see <a href="http://reactivex.io/documentation/operators/catch.html">ReactiveX operators documentation: Catch</a> */ public final Observable<T> onErrorResumeNext(final Observable<? extends T> resumeSequence) { return lift(new OperatorOnErrorResumeNextViaObservable<T>(resumeSequence)); } /** * Instructs an Observable to emit an item (returned by a specified function) rather than invoking * {@link Observer#onError onError} if it encounters an error. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/onErrorReturn.png" alt=""> * <p> * By default, when an Observable encounters an error that prevents it from emitting the expected item to * its {@link Observer}, the Observable invokes its Observer's {@code onError} method, and then quits * without invoking any more of its Observer's methods. The {@code onErrorReturn} method changes this * behavior. If you pass a function ({@code resumeFunction}) to an Observable's {@code onErrorReturn} * method, if the original Observable encounters an error, instead of invoking its Observer's * {@code onError} method, it will instead emit the return value of {@code resumeFunction}. * <p> * You can use this to prevent errors from propagating or to supply fallback data should errors be * encountered. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onErrorReturn} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param resumeFunction * a function that returns an item that the new Observable will emit if the source Observable * encounters an error * @return the original Observable with appropriately modified behavior * @see <a href="http://reactivex.io/documentation/operators/catch.html">ReactiveX operators documentation: Catch</a> */ public final Observable<T> onErrorReturn(Func1<Throwable, ? extends T> resumeFunction) { return lift(new OperatorOnErrorReturn<T>(resumeFunction)); } /** * Instructs an Observable to pass control to another Observable rather than invoking * {@link Observer#onError onError} if it encounters an {@link java.lang.Exception}. * <p> * This differs from {@link #onErrorResumeNext} in that this one does not handle {@link java.lang.Throwable} * or {@link java.lang.Error} but lets those continue through. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/onExceptionResumeNextViaObservable.png" alt=""> * <p> * By default, when an Observable encounters an exception that prevents it from emitting the expected item * to its {@link Observer}, the Observable invokes its Observer's {@code onError} method, and then quits * without invoking any more of its Observer's methods. The {@code onExceptionResumeNext} method changes * this behavior. If you pass another Observable ({@code resumeSequence}) to an Observable's * {@code onExceptionResumeNext} method, if the original Observable encounters an exception, instead of * invoking its Observer's {@code onError} method, it will instead relinquish control to * {@code resumeSequence} which will invoke the Observer's {@link Observer#onNext onNext} method if it is * able to do so. In such a case, because no Observable necessarily invokes {@code onError}, the Observer * may never know that an exception happened. * <p> * You can use this to prevent exceptions from propagating or to supply fallback data should exceptions be * encountered. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code onErrorResumeNext} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param resumeSequence * a function that returns an Observable that will take over if the source Observable encounters * an exception * @return the original Observable, with appropriately modified behavior * @see <a href="http://reactivex.io/documentation/operators/catch.html">ReactiveX operators documentation: Catch</a> */ public final Observable<T> onExceptionResumeNext(final Observable<? extends T> resumeSequence) { return lift(new OperatorOnExceptionResumeNextViaObservable<T>(resumeSequence)); } /** * Returns a {@link ConnectableObservable}, which is a variety of Observable that waits until its * {@link ConnectableObservable#connect connect} method is called before it begins emitting items to those * {@link Observer}s that have subscribed to it. * <p> * <img width="640" height="510" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/publishConnect.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code publish} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return a {@link ConnectableObservable} that upon connection causes the source Observable to emit items * to its {@link Observer}s * @see <a href="http://reactivex.io/documentation/operators/publish.html">ReactiveX operators documentation: Publish</a> */ public final ConnectableObservable<T> publish() { return OperatorPublish.create(this); } /** * Returns an Observable that emits the results of invoking a specified selector on items emitted by a * {@link ConnectableObservable} that shares a single subscription to the underlying sequence. * <p> * <img width="640" height="510" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/publishConnect.f.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code publish} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * a function that can use the multicasted source sequence as many times as needed, without * causing multiple subscriptions to the source sequence. Subscribers to the given source will * receive all notifications of the source from the time of the subscription forward. * @return an Observable that emits the results of invoking the selector on the items emitted by a {@link ConnectableObservable} that shares a single subscription to the underlying sequence * @see <a href="http://reactivex.io/documentation/operators/publish.html">ReactiveX operators documentation: Publish</a> */ public final <R> Observable<R> publish(Func1<? super Observable<T>, ? extends Observable<R>> selector) { return OperatorPublish.create(this, selector); } /** * Returns an Observable that applies a specified accumulator function to the first item emitted by a source * Observable, then feeds the result of that function along with the second item emitted by the source * Observable into the same function, and so on until all items have been emitted by the source Observable, * and emits the final result from the final call to your function as its sole item. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/reduce.png" alt=""> * <p> * This technique, which is called "reduce" here, is sometimes called "aggregate," "fold," "accumulate," * "compress," or "inject" in other programming contexts. Groovy, for instance, has an {@code inject} method * that does a similar operation on lists. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because by intent it will receive all values and reduce * them to a single {@code onNext}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code reduce} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param accumulator * an accumulator function to be invoked on each item emitted by the source Observable, whose * result will be used in the next accumulator call * @return an Observable that emits a single item that is the result of accumulating the items emitted by * the source Observable * @throws IllegalArgumentException * if the source Observable emits no items * @see <a href="http://reactivex.io/documentation/operators/reduce.html">ReactiveX operators documentation: Reduce</a> * @see <a href="http://en.wikipedia.org/wiki/Fold_(higher-order_function)">Wikipedia: Fold (higher-order function)</a> */ public final Observable<T> reduce(Func2<T, T, T> accumulator) { /* * Discussion and confirmation of implementation at * https://github.com/ReactiveX/RxJava/issues/423#issuecomment-27642532 * * It should use last() not takeLast(1) since it needs to emit an error if the sequence is empty. */ return scan(accumulator).last(); } /** * Returns an Observable that applies a specified accumulator function to the first item emitted by a source * Observable and a specified seed value, then feeds the result of that function along with the second item * emitted by an Observable into the same function, and so on until all items have been emitted by the * source Observable, emitting the final result from the final call to your function as its sole item. * <p> * <img width="640" height="325" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/reduceSeed.png" alt=""> * <p> * This technique, which is called "reduce" here, is sometimec called "aggregate," "fold," "accumulate," * "compress," or "inject" in other programming contexts. Groovy, for instance, has an {@code inject} method * that does a similar operation on lists. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because by intent it will receive all values and reduce * them to a single {@code onNext}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code reduce} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param initialValue * the initial (seed) accumulator value * @param accumulator * an accumulator function to be invoked on each item emitted by the source Observable, the * result of which will be used in the next accumulator call * @return an Observable that emits a single item that is the result of accumulating the output from the * items emitted by the source Observable * @see <a href="http://reactivex.io/documentation/operators/reduce.html">ReactiveX operators documentation: Reduce</a> * @see <a href="http://en.wikipedia.org/wiki/Fold_(higher-order_function)">Wikipedia: Fold (higher-order function)</a> */ public final <R> Observable<R> reduce(R initialValue, Func2<R, ? super T, R> accumulator) { return scan(initialValue, accumulator).takeLast(1); } /** * Returns an Observable that repeats the sequence of items emitted by the source Observable indefinitely. * <p> * <img width="640" height="309" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/repeat.o.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code repeat} operates by default on the {@code trampoline} {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits the items emitted by the source Observable repeatedly and in sequence * @see <a href="http://reactivex.io/documentation/operators/repeat.html">ReactiveX operators documentation: Repeat</a> */ public final Observable<T> repeat() { return OnSubscribeRedo.<T>repeat(this); } /** * Returns an Observable that repeats the sequence of items emitted by the source Observable indefinitely, * on a particular Scheduler. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/repeat.os.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param scheduler * the Scheduler to emit the items on * @return an Observable that emits the items emitted by the source Observable repeatedly and in sequence * @see <a href="http://reactivex.io/documentation/operators/repeat.html">ReactiveX operators documentation: Repeat</a> */ public final Observable<T> repeat(Scheduler scheduler) { return OnSubscribeRedo.<T>repeat(this, scheduler); } /** * Returns an Observable that repeats the sequence of items emitted by the source Observable at most * {@code count} times. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/repeat.on.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code repeat} operates by default on the {@code trampoline} {@link Scheduler}.</dd> * </dl> * * @param count * the number of times the source Observable items are repeated, a count of 0 will yield an empty * sequence * @return an Observable that repeats the sequence of items emitted by the source Observable at most * {@code count} times * @throws IllegalArgumentException * if {@code count} is less than zero * @see <a href="http://reactivex.io/documentation/operators/repeat.html">ReactiveX operators documentation: Repeat</a> */ public final Observable<T> repeat(final long count) { return OnSubscribeRedo.<T>repeat(this, count); } /** * Returns an Observable that repeats the sequence of items emitted by the source Observable at most * {@code count} times, on a particular Scheduler. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/repeat.ons.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param count * the number of times the source Observable items are repeated, a count of 0 will yield an empty * sequence * @param scheduler * the {@link Scheduler} to emit the items on * @return an Observable that repeats the sequence of items emitted by the source Observable at most * {@code count} times on a particular Scheduler * @see <a href="http://reactivex.io/documentation/operators/repeat.html">ReactiveX operators documentation: Repeat</a> */ public final Observable<T> repeat(final long count, Scheduler scheduler) { return OnSubscribeRedo.<T>repeat(this, count, scheduler); } /** * Returns an Observable that emits the same values as the source Observable with the exception of an * {@code onCompleted}. An {@code onCompleted} notification from the source will result in the emission of * a {@code void} item to the Observable provided as an argument to the {@code notificationHandler} * function. If that Observable calls {@code onComplete} or {@code onError} then {@code repeatWhen} will * call {@code onCompleted} or {@code onError} on the child subscription. Otherwise, this Observable will * resubscribe to the source Observable, on a particular Scheduler. * <p> * <img width="640" height="430" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/repeatWhen.f.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param notificationHandler * receives an Observable of notifications with which a user can complete or error, aborting the repeat. * @param scheduler * the {@link Scheduler} to emit the items on * @return the source Observable modified with repeat logic * @see <a href="http://reactivex.io/documentation/operators/repeat.html">ReactiveX operators documentation: Repeat</a> */ public final Observable<T> repeatWhen(final Func1<? super Observable<? extends Void>, ? extends Observable<?>> notificationHandler, Scheduler scheduler) { Func1<? super Observable<? extends Notification<?>>, ? extends Observable<?>> dematerializedNotificationHandler = new Func1<Observable<? extends Notification<?>>, Observable<?>>() { @Override public Observable<?> call(Observable<? extends Notification<?>> notifications) { return notificationHandler.call(notifications.map(new Func1<Notification<?>, Void>() { @Override public Void call(Notification<?> notification) { return null; } })); } }; return OnSubscribeRedo.repeat(this, dematerializedNotificationHandler, scheduler); } /** * Returns an Observable that emits the same values as the source Observable with the exception of an * {@code onCompleted}. An {@code onCompleted} notification from the source will result in the emission of * a {@code void} item to the Observable provided as an argument to the {@code notificationHandler} * function. If that Observable calls {@code onComplete} or {@code onError} then {@code repeatWhen} will * call {@code onCompleted} or {@code onError} on the child subscription. Otherwise, this Observable will * resubscribe to the source observable. * <p> * <img width="640" height="430" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/repeatWhen.f.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code repeatWhen} operates by default on the {@code trampoline} {@link Scheduler}.</dd> * </dl> * * @param notificationHandler * receives an Observable of notifications with which a user can complete or error, aborting the repeat. * @return the source Observable modified with repeat logic * @see <a href="http://reactivex.io/documentation/operators/repeat.html">ReactiveX operators documentation: Repeat</a> */ public final Observable<T> repeatWhen(final Func1<? super Observable<? extends Void>, ? extends Observable<?>> notificationHandler) { Func1<? super Observable<? extends Notification<?>>, ? extends Observable<?>> dematerializedNotificationHandler = new Func1<Observable<? extends Notification<?>>, Observable<?>>() { @Override public Observable<?> call(Observable<? extends Notification<?>> notifications) { return notificationHandler.call(notifications.map(new Func1<Notification<?>, Void>() { @Override public Void call(Notification<?> notification) { return null; } })); } }; return OnSubscribeRedo.repeat(this, dematerializedNotificationHandler); } /** * Returns a {@link ConnectableObservable} that shares a single subscription to the underlying Observable * that will replay all of its items and notifications to any future {@link Observer}. A Connectable * Observable resembles an ordinary Observable, except that it does not begin emitting items when it is * subscribed to, but only when its {@code connect} method is called. * <p> * <img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code replay} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return a {@link ConnectableObservable} that upon connection causes the source Observable to emit its * items to its {@link Observer}s * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final ConnectableObservable<T> replay() { return new OperatorMulticast<T, T>(this, new Func0<Subject<? super T, ? extends T>>() { @Override public Subject<? super T, ? extends T> call() { return ReplaySubject.<T> create(); } }); } /** * Returns an Observable that emits items that are the results of invoking a specified selector on the items * emitted by a {@link ConnectableObservable} that shares a single subscription to the source Observable. * <p> * <img width="640" height="450" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.f.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code replay} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * the selector function, which can use the multicasted sequence as many times as needed, without * causing multiple subscriptions to the Observable * @return an Observable that emits items that are the results of invoking the selector on a * {@link ConnectableObservable} that shares a single subscription to the source Observable * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final <R> Observable<R> replay(Func1<? super Observable<T>, ? extends Observable<R>> selector) { return create(new OnSubscribeMulticastSelector<T, T, R>(this, new Func0<Subject<T, T>>() { @Override public final Subject<T, T> call() { return ReplaySubject.create(); } }, selector)); } /** * Returns an Observable that emits items that are the results of invoking a specified selector on items * emitted by a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying {@code bufferSize} notifications. * <p> * <img width="640" height="440" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.fn.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code replay} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * the selector function, which can use the multicasted sequence as many times as needed, without * causing multiple subscriptions to the Observable * @param bufferSize * the buffer size that limits the number of items the connectable observable can replay * @return an Observable that emits items that are the results of invoking the selector on items emitted by * a {@link ConnectableObservable} that shares a single subscription to the source Observable * replaying no more than {@code bufferSize} items * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final <R> Observable<R> replay(Func1<? super Observable<T>, ? extends Observable<R>> selector, final int bufferSize) { return create(new OnSubscribeMulticastSelector<T, T, R>(this, new Func0<Subject<T, T>>() { @Override public final Subject<T, T> call() { return ReplaySubject.<T>createWithSize(bufferSize); } }, selector)); } /** * Returns an Observable that emits items that are the results of invoking a specified selector on items * emitted by a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying no more than {@code bufferSize} items that were emitted within a specified time window. * <p> * <img width="640" height="445" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.fnt.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code replay} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * a selector function, which can use the multicasted sequence as many times as needed, without * causing multiple subscriptions to the Observable * @param bufferSize * the buffer size that limits the number of items the connectable observable can replay * @param time * the duration of the window in which the replayed items must have been emitted * @param unit * the time unit of {@code time} * @return an Observable that emits items that are the results of invoking the selector on items emitted by * a {@link ConnectableObservable} that shares a single subscription to the source Observable, and * replays no more than {@code bufferSize} items that were emitted within the window defined by * {@code time} * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final <R> Observable<R> replay(Func1<? super Observable<T>, ? extends Observable<R>> selector, int bufferSize, long time, TimeUnit unit) { return replay(selector, bufferSize, time, unit, Schedulers.computation()); } /** * Returns an Observable that emits items that are the results of invoking a specified selector on items * emitted by a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying no more than {@code bufferSize} items that were emitted within a specified time window. * <p> * <img width="640" height="445" height="440" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.fnts.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * a selector function, which can use the multicasted sequence as many times as needed, without * causing multiple subscriptions to the Observable * @param bufferSize * the buffer size that limits the number of items the connectable observable can replay * @param time * the duration of the window in which the replayed items must have been emitted * @param unit * the time unit of {@code time} * @param scheduler * the Scheduler that is the time source for the window * @return an Observable that emits items that are the results of invoking the selector on items emitted by * a {@link ConnectableObservable} that shares a single subscription to the source Observable, and * replays no more than {@code bufferSize} items that were emitted within the window defined by * {@code time} * @throws IllegalArgumentException * if {@code bufferSize} is less than zero * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final <R> Observable<R> replay(Func1<? super Observable<T>, ? extends Observable<R>> selector, final int bufferSize, final long time, final TimeUnit unit, final Scheduler scheduler) { if (bufferSize < 0) { throw new IllegalArgumentException("bufferSize < 0"); } return create(new OnSubscribeMulticastSelector<T, T, R>(this, new Func0<Subject<T, T>>() { @Override public final Subject<T, T> call() { return ReplaySubject.<T>createWithTimeAndSize(time, unit, bufferSize, scheduler); } }, selector)); } /** * Returns an Observable that emits items that are the results of invoking a specified selector on items * emitted by a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying a maximum of {@code bufferSize} items. * <p> * <img width="640" height="440" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.fns.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * a selector function, which can use the multicasted sequence as many times as needed, without * causing multiple subscriptions to the Observable * @param bufferSize * the buffer size that limits the number of items the connectable observable can replay * @param scheduler * the Scheduler on which the replay is observed * @return an Observable that emits items that are the results of invoking the selector on items emitted by * a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying no more than {@code bufferSize} notifications * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final <R> Observable<R> replay(Func1<? super Observable<T>, ? extends Observable<R>> selector, final int bufferSize, final Scheduler scheduler) { return create(new OnSubscribeMulticastSelector<T, T, R>(this, new Func0<Subject<T, T>>() { @Override public final Subject<T, T> call() { return OperatorReplay.<T> createScheduledSubject(ReplaySubject.<T>createWithSize(bufferSize), scheduler); } }, selector)); } /** * Returns an Observable that emits items that are the results of invoking a specified selector on items * emitted by a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying all items that were emitted within a specified time window. * <p> * <img width="640" height="435" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.ft.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code replay} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * a selector function, which can use the multicasted sequence as many times as needed, without * causing multiple subscriptions to the Observable * @param time * the duration of the window in which the replayed items must have been emitted * @param unit * the time unit of {@code time} * @return an Observable that emits items that are the results of invoking the selector on items emitted by * a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying all items that were emitted within the window defined by {@code time} * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final <R> Observable<R> replay(Func1<? super Observable<T>, ? extends Observable<R>> selector, long time, TimeUnit unit) { return replay(selector, time, unit, Schedulers.computation()); } /** * Returns an Observable that emits items that are the results of invoking a specified selector on items * emitted by a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying all items that were emitted within a specified time window. * <p> * <img width="640" height="440" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.fts.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * a selector function, which can use the multicasted sequence as many times as needed, without * causing multiple subscriptions to the Observable * @param time * the duration of the window in which the replayed items must have been emitted * @param unit * the time unit of {@code time} * @param scheduler * the scheduler that is the time source for the window * @return an Observable that emits items that are the results of invoking the selector on items emitted by * a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying all items that were emitted within the window defined by {@code time} * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final <R> Observable<R> replay(Func1<? super Observable<T>, ? extends Observable<R>> selector, final long time, final TimeUnit unit, final Scheduler scheduler) { return create(new OnSubscribeMulticastSelector<T, T, R>(this, new Func0<Subject<T, T>>() { @Override public final Subject<T, T> call() { return ReplaySubject.<T>createWithTime(time, unit, scheduler); } }, selector)); } /** * Returns an Observable that emits items that are the results of invoking a specified selector on items * emitted by a {@link ConnectableObservable} that shares a single subscription to the source Observable. * <p> * <img width="640" height="445" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.fs.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param <R> * the type of items emitted by the resulting Observable * @param selector * a selector function, which can use the multicasted sequence as many times as needed, without * causing multiple subscriptions to the Observable * @param scheduler * the Scheduler where the replay is observed * @return an Observable that emits items that are the results of invoking the selector on items emitted by * a {@link ConnectableObservable} that shares a single subscription to the source Observable, * replaying all items * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final <R> Observable<R> replay(Func1<? super Observable<T>, ? extends Observable<R>> selector, final Scheduler scheduler) { return create(new OnSubscribeMulticastSelector<T, T, R>(this, new Func0<Subject<T, T>>() { @Override public final Subject<T, T> call() { return OperatorReplay.createScheduledSubject(ReplaySubject.<T> create(), scheduler); } }, selector)); } /** * Returns a {@link ConnectableObservable} that shares a single subscription to the source Observable that * replays at most {@code bufferSize} items emitted by that Observable. A Connectable Observable resembles * an ordinary Observable, except that it does not begin emitting items when it is subscribed to, but only * when its {@code connect} method is called. * <p> * <img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.n.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code replay} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param bufferSize * the buffer size that limits the number of items that can be replayed * @return a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays at most {@code bufferSize} items emitted by that Observable * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final ConnectableObservable<T> replay(final int bufferSize) { return new OperatorMulticast<T, T>(this, new Func0<Subject<? super T, ? extends T>>() { @Override public Subject<? super T, ? extends T> call() { return ReplaySubject.<T>createWithSize(bufferSize); } }); } /** * Returns a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays at most {@code bufferSize} items that were emitted during a specified time window. A Connectable * Observable resembles an ordinary Observable, except that it does not begin emitting items when it is * subscribed to, but only when its {@code connect} method is called. * <p> * <img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.nt.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code replay} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param bufferSize * the buffer size that limits the number of items that can be replayed * @param time * the duration of the window in which the replayed items must have been emitted * @param unit * the time unit of {@code time} * @return a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays at most {@code bufferSize} items that were emitted during the window defined by * {@code time} * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final ConnectableObservable<T> replay(int bufferSize, long time, TimeUnit unit) { return replay(bufferSize, time, unit, Schedulers.computation()); } /** * Returns a {@link ConnectableObservable} that shares a single subscription to the source Observable and * that replays a maximum of {@code bufferSize} items that are emitted within a specified time window. A * Connectable Observable resembles an ordinary Observable, except that it does not begin emitting items * when it is subscribed to, but only when its {@code connect} method is called. * <p> * <img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.nts.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param bufferSize * the buffer size that limits the number of items that can be replayed * @param time * the duration of the window in which the replayed items must have been emitted * @param unit * the time unit of {@code time} * @param scheduler * the scheduler that is used as a time source for the window * @return a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays at most {@code bufferSize} items that were emitted during the window defined by * {@code time} * @throws IllegalArgumentException * if {@code bufferSize} is less than zero * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final ConnectableObservable<T> replay(final int bufferSize, final long time, final TimeUnit unit, final Scheduler scheduler) { if (bufferSize < 0) { throw new IllegalArgumentException("bufferSize < 0"); } return new OperatorMulticast<T, T>(this, new Func0<Subject<? super T, ? extends T>>() { @Override public Subject<? super T, ? extends T> call() { return ReplaySubject.<T>createWithTimeAndSize(time, unit, bufferSize, scheduler); } }); } /** * Returns a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays at most {@code bufferSize} items emitted by that Observable. A Connectable Observable resembles * an ordinary Observable, except that it does not begin emitting items when it is subscribed to, but only * when its {@code connect} method is called. * <p> * <img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.ns.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param bufferSize * the buffer size that limits the number of items that can be replayed * @param scheduler * the scheduler on which the Observers will observe the emitted items * @return a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays at most {@code bufferSize} items that were emitted by the Observable * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final ConnectableObservable<T> replay(final int bufferSize, final Scheduler scheduler) { return new OperatorMulticast<T, T>(this, new Func0<Subject<? super T, ? extends T>>() { @Override public Subject<? super T, ? extends T> call() { return OperatorReplay.createScheduledSubject(ReplaySubject.<T>createWithSize(bufferSize), scheduler); } }); } /** * Returns a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays all items emitted by that Observable within a specified time window. A Connectable Observable * resembles an ordinary Observable, except that it does not begin emitting items when it is subscribed to, * but only when its {@code connect} method is called. * <p> * <img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.t.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code replay} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param time * the duration of the window in which the replayed items must have been emitted * @param unit * the time unit of {@code time} * @return a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays the items that were emitted during the window defined by {@code time} * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final ConnectableObservable<T> replay(long time, TimeUnit unit) { return replay(time, unit, Schedulers.computation()); } /** * Returns a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays all items emitted by that Observable within a specified time window. A Connectable Observable * resembles an ordinary Observable, except that it does not begin emitting items when it is subscribed to, * but only when its {@code connect} method is called. * <p> * <img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.ts.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param time * the duration of the window in which the replayed items must have been emitted * @param unit * the time unit of {@code time} * @param scheduler * the Scheduler that is the time source for the window * @return a {@link ConnectableObservable} that shares a single subscription to the source Observable and * replays the items that were emitted during the window defined by {@code time} * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final ConnectableObservable<T> replay(final long time, final TimeUnit unit, final Scheduler scheduler) { return new OperatorMulticast<T, T>(this, new Func0<Subject<? super T, ? extends T>>() { @Override public Subject<? super T, ? extends T> call() { return ReplaySubject.<T>createWithTime(time, unit, scheduler); } }); } /** * Returns a {@link ConnectableObservable} that shares a single subscription to the source Observable that * will replay all of its items and notifications to any future {@link Observer} on the given * {@link Scheduler}. A Connectable Observable resembles an ordinary Observable, except that it does not * begin emitting items when it is subscribed to, but only when its {@code connect} method is called. * <p> * <img width="640" height="515" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/replay.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param scheduler * the Scheduler on which the Observers will observe the emitted items * @return a {@link ConnectableObservable} that shares a single subscription to the source Observable that * will replay all of its items and notifications to any future {@link Observer} on the given * {@link Scheduler} * @see <a href="http://reactivex.io/documentation/operators/replay.html">ReactiveX operators documentation: Replay</a> */ public final ConnectableObservable<T> replay(final Scheduler scheduler) { return new OperatorMulticast<T, T>(this, new Func0<Subject<? super T, ? extends T>>() { @Override public Subject<? super T, ? extends T> call() { return OperatorReplay.createScheduledSubject(ReplaySubject.<T> create(), scheduler); } }); } /** * Returns an Observable that mirrors the source Observable, resubscribing to it if it calls {@code onError} * (infinite retry count). * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/retry.png" alt=""> * <p> * If the source Observable calls {@link Observer#onError}, this method will resubscribe to the source * Observable rather than propagating the {@code onError} call. * <p> * Any and all items emitted by the source Observable will be emitted by the resulting Observable, even * those emitted during failed subscriptions. For example, if an Observable fails at first but emits * {@code [1, 2]} then succeeds the second time and emits {@code [1, 2, 3, 4, 5]} then the complete sequence * of emissions and notifications would be {@code [1, 2, 1, 2, 3, 4, 5, onCompleted]}. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code retry} operates by default on the {@code trampoline} {@link Scheduler}.</dd> * </dl> * * @return the source Observable modified with retry logic * @see <a href="http://reactivex.io/documentation/operators/retry.html">ReactiveX operators documentation: Retry</a> */ public final Observable<T> retry() { return OnSubscribeRedo.<T>retry(this); } /** * Returns an Observable that mirrors the source Observable, resubscribing to it if it calls {@code onError} * up to a specified number of retries. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/retry.png" alt=""> * <p> * If the source Observable calls {@link Observer#onError}, this method will resubscribe to the source * Observable for a maximum of {@code count} resubscriptions rather than propagating the * {@code onError} call. * <p> * Any and all items emitted by the source Observable will be emitted by the resulting Observable, even * those emitted during failed subscriptions. For example, if an Observable fails at first but emits * {@code [1, 2]} then succeeds the second time and emits {@code [1, 2, 3, 4, 5]} then the complete sequence * of emissions and notifications would be {@code [1, 2, 1, 2, 3, 4, 5, onCompleted]}. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code retry} operates by default on the {@code trampoline} {@link Scheduler}.</dd> * </dl> * * @param count * number of retry attempts before failing * @return the source Observable modified with retry logic * @see <a href="http://reactivex.io/documentation/operators/retry.html">ReactiveX operators documentation: Retry</a> */ public final Observable<T> retry(final long count) { return OnSubscribeRedo.<T>retry(this, count); } /** * Returns an Observable that mirrors the source Observable, resubscribing to it if it calls {@code onError} * and the predicate returns true for that specific exception and retry count. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/retry.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code retry} operates by default on the {@code trampoline} {@link Scheduler}.</dd> * </dl> * * @param predicate * the predicate that determines if a resubscription may happen in case of a specific exception * and retry count * @return the source Observable modified with retry logic * @see #retry() * @see <a href="http://reactivex.io/documentation/operators/retry.html">ReactiveX operators documentation: Retry</a> */ public final Observable<T> retry(Func2<Integer, Throwable, Boolean> predicate) { return nest().lift(new OperatorRetryWithPredicate<T>(predicate)); } /** * Returns an Observable that emits the same values as the source observable with the exception of an * {@code onError}. An {@code onError} notification from the source will result in the emission of a * {@link Throwable} item to the Observable provided as an argument to the {@code notificationHandler} * function. If that Observable calls {@code onComplete} or {@code onError} then {@code retry} will call * {@code onCompleted} or {@code onError} on the child subscription. Otherwise, this Observable will * resubscribe to the source Observable. * <p> * <img width="640" height="430" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/retryWhen.f.png" alt=""> * * Example: * * This retries 3 times, each time incrementing the number of seconds it waits. * * <pre> {@code * Observable.create((Subscriber<? super String> s) -> { * System.out.println("subscribing"); * s.onError(new RuntimeException("always fails")); * }).retryWhen(attempts -> { * return attempts.zipWith(Observable.range(1, 3), (n, i) -> i).flatMap(i -> { * System.out.println("delay retry by " + i + " second(s)"); * return Observable.timer(i, TimeUnit.SECONDS); * }); * }).toBlocking().forEach(System.out::println); * } </pre> * * Output is: * * <pre> {@code * subscribing * delay retry by 1 second(s) * subscribing * delay retry by 2 second(s) * subscribing * delay retry by 3 second(s) * subscribing * } </pre> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code retryWhen} operates by default on the {@code trampoline} {@link Scheduler}.</dd> * </dl> * * @param notificationHandler * receives an Observable of notifications with which a user can complete or error, aborting the * retry * @return the source Observable modified with retry logic * @see <a href="http://reactivex.io/documentation/operators/retry.html">ReactiveX operators documentation: Retry</a> */ public final Observable<T> retryWhen(final Func1<? super Observable<? extends Throwable>, ? extends Observable<?>> notificationHandler) { Func1<? super Observable<? extends Notification<?>>, ? extends Observable<?>> dematerializedNotificationHandler = new Func1<Observable<? extends Notification<?>>, Observable<?>>() { @Override public Observable<?> call(Observable<? extends Notification<?>> notifications) { return notificationHandler.call(notifications.map(new Func1<Notification<?>, Throwable>() { @Override public Throwable call(Notification<?> notification) { return notification.getThrowable(); } })); } }; return OnSubscribeRedo.<T> retry(this, dematerializedNotificationHandler); } /** * Returns an Observable that emits the same values as the source observable with the exception of an * {@code onError}. An {@code onError} will cause the emission of the {@link Throwable} that cause the * error to the Observable returned from {@code notificationHandler}. If that Observable calls * {@code onComplete} or {@code onError} then {@code retry} will call {@code onCompleted} or {@code onError} * on the child subscription. Otherwise, this Observable will resubscribe to the source observable, on a * particular Scheduler. * <p> * <img width="640" height="430" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/retryWhen.f.png" alt=""> * <p> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param notificationHandler * receives an Observable of notifications with which a user can complete or error, aborting the * retry * @param scheduler * the {@link Scheduler} on which to subscribe to the source Observable * @return the source Observable modified with retry logic * @see <a href="http://reactivex.io/documentation/operators/retry.html">ReactiveX operators documentation: Retry</a> */ public final Observable<T> retryWhen(final Func1<? super Observable<? extends Throwable>, ? extends Observable<?>> notificationHandler, Scheduler scheduler) { Func1<? super Observable<? extends Notification<?>>, ? extends Observable<?>> dematerializedNotificationHandler = new Func1<Observable<? extends Notification<?>>, Observable<?>>() { @Override public Observable<?> call(Observable<? extends Notification<?>> notifications) { return notificationHandler.call(notifications.map(new Func1<Notification<?>, Throwable>() { @Override public Throwable call(Notification<?> notification) { return notification.getThrowable(); } })); } }; return OnSubscribeRedo.<T> retry(this, dematerializedNotificationHandler, scheduler); } /** * Returns an Observable that emits the most recently emitted item (if any) emitted by the source Observable * within periodic time intervals. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code sample} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param period * the sampling rate * @param unit * the {@link TimeUnit} in which {@code period} is defined * @return an Observable that emits the results of sampling the items emitted by the source Observable at * the specified time interval * @see <a href="http://reactivex.io/documentation/operators/sample.html">ReactiveX operators documentation: Sample</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> * @see #throttleLast(long, TimeUnit) */ public final Observable<T> sample(long period, TimeUnit unit) { return sample(period, unit, Schedulers.computation()); } /** * Returns an Observable that emits the most recently emitted item (if any) emitted by the source Observable * within periodic time intervals, where the intervals are defined on a particular Scheduler. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param period * the sampling rate * @param unit * the {@link TimeUnit} in which {@code period} is defined * @param scheduler * the {@link Scheduler} to use when sampling * @return an Observable that emits the results of sampling the items emitted by the source Observable at * the specified time interval * @see <a href="http://reactivex.io/documentation/operators/sample.html">ReactiveX operators documentation: Sample</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> * @see #throttleLast(long, TimeUnit, Scheduler) */ public final Observable<T> sample(long period, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorSampleWithTime<T>(period, unit, scheduler)); } /** * Returns an Observable that, when the specified {@code sampler} Observable emits an item or completes, * emits the most recently emitted item (if any) emitted by the source Observable since the previous * emission from the {@code sampler} Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/sample.o.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses the emissions of the {@code sampler} * Observable to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code sample} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param sampler * the Observable to use for sampling the source Observable * @return an Observable that emits the results of sampling the items emitted by this Observable whenever * the {@code sampler} Observable emits an item or completes * @see <a href="http://reactivex.io/documentation/operators/sample.html">ReactiveX operators documentation: Sample</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> */ public final <U> Observable<T> sample(Observable<U> sampler) { return lift(new OperatorSampleWithObservable<T, U>(sampler)); } /** * Returns an Observable that applies a specified accumulator function to the first item emitted by a source * Observable, then feeds the result of that function along with the second item emitted by the source * Observable into the same function, and so on until all items have been emitted by the source Observable, * emitting the result of each of these iterations. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/scan.png" alt=""> * <p> * This sort of function is sometimes called an accumulator. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code scan} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param accumulator * an accumulator function to be invoked on each item emitted by the source Observable, whose * result will be emitted to {@link Observer}s via {@link Observer#onNext onNext} and used in the * next accumulator call * @return an Observable that emits the results of each call to the accumulator function * @see <a href="http://reactivex.io/documentation/operators/scan.html">ReactiveX operators documentation: Scan</a> */ public final Observable<T> scan(Func2<T, T, T> accumulator) { return lift(new OperatorScan<T, T>(accumulator)); } /** * Returns an Observable that applies a specified accumulator function to the first item emitted by a source * Observable and a seed value, then feeds the result of that function along with the second item emitted by * the source Observable into the same function, and so on until all items have been emitted by the source * Observable, emitting the result of each of these iterations. * <p> * <img width="640" height="320" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/scanSeed.png" alt=""> * <p> * This sort of function is sometimes called an accumulator. * <p> * Note that the Observable that results from this method will emit {@code initialValue} as its first * emitted item. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code scan} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param initialValue * the initial (seed) accumulator item * @param accumulator * an accumulator function to be invoked on each item emitted by the source Observable, whose * result will be emitted to {@link Observer}s via {@link Observer#onNext onNext} and used in the * next accumulator call * @return an Observable that emits {@code initialValue} followed by the results of each call to the * accumulator function * @see <a href="http://reactivex.io/documentation/operators/scan.html">ReactiveX operators documentation: Scan</a> */ public final <R> Observable<R> scan(R initialValue, Func2<R, ? super T, R> accumulator) { return lift(new OperatorScan<R, T>(initialValue, accumulator)); } /** * Forces an Observable's emissions and notifications to be serialized and for it to obey the Rx contract * in other ways. * <p> * It is possible for an Observable to invoke its Subscribers' methods asynchronously, perhaps from * different threads. This could make such an Observable poorly-behaved, in that it might try to invoke * {@code onCompleted} or {@code onError} before one of its {@code onNext} invocations, or it might call * {@code onNext} from two different threads concurrently. You can force such an Observable to be * well-behaved and sequential by applying the {@code serialize} method to it. * <p> * <img width="640" height="400" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/synchronize.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code serialize} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an {@link Observable} that is guaranteed to be well-behaved and to make only serialized calls to * its observers * @see <a href="http://reactivex.io/documentation/operators/serialize.html">ReactiveX operators documentation: Serialize</a> */ public final Observable<T> serialize() { return lift(OperatorSerialize.<T>instance()); } /** * Returns a new {@link Observable} that multicasts (shares) the original {@link Observable}. As long as * there is at least one {@link Subscriber} this {@link Observable} will be subscribed and emitting data. * When all subscribers have unsubscribed it will unsubscribe from the source {@link Observable}. * <p> * This is an alias for {@link #publish()}.{@link ConnectableObservable#refCount()}. * <p> * <img width="640" height="510" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/publishRefCount.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure because multicasting means the stream is "hot" with * multiple subscribers. Each child will need to manage backpressure independently using operators such * as {@link #onBackpressureDrop} and {@link #onBackpressureBuffer}.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code share} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an {@code Observable} that upon connection causes the source {@code Observable} to emit items * to its {@link Observer}s * @see <a href="http://reactivex.io/documentation/operators/refcount.html">ReactiveX operators documentation: RefCount</a> */ public final Observable<T> share() { return publish().refCount(); } /** * Returns an Observable that emits the single item emitted by the source Observable, if that Observable * emits only a single item. If the source Observable emits more than one item or no items, notify of an * {@code IllegalArgumentException} or {@code NoSuchElementException} respectively. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/single.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code single} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits the single item emitted by the source Observable * @throws IllegalArgumentException * if the source emits more than one item * @throws NoSuchElementException * if the source emits no items * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> single() { return lift(new OperatorSingle<T>()); } /** * Returns an Observable that emits the single item emitted by the source Observable that matches a * specified predicate, if that Observable emits one such item. If the source Observable emits more than one * such item or no such items, notify of an {@code IllegalArgumentException} or * {@code NoSuchElementException} respectively. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/single.p.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code single} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * a predicate function to evaluate items emitted by the source Observable * @return an Observable that emits the single item emitted by the source Observable that matches the * predicate * @throws IllegalArgumentException * if the source Observable emits more than one item that matches the predicate * @throws NoSuchElementException * if the source Observable emits no item that matches the predicate * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> single(Func1<? super T, Boolean> predicate) { return filter(predicate).single(); } /** * Returns an Observable that emits the single item emitted by the source Observable, if that Observable * emits only a single item, or a default item if the source Observable emits no items. If the source * Observable emits more than one item, throw an {@code IllegalArgumentException}. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/singleOrDefault.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code singleOrDefault} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param defaultValue * a default value to emit if the source Observable emits no item * @return an Observable that emits the single item emitted by the source Observable, or a default item if * the source Observable is empty * @throws IllegalArgumentException * if the source Observable emits more than one item * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> singleOrDefault(T defaultValue) { return lift(new OperatorSingle<T>(defaultValue)); } /** * Returns an Observable that emits the single item emitted by the source Observable that matches a * predicate, if that Observable emits only one such item, or a default item if the source Observable emits * no such items. If the source Observable emits more than one such item, throw an * {@code IllegalArgumentException}. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/singleOrDefault.p.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code singleOrDefault} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param defaultValue * a default item to emit if the source Observable emits no matching items * @param predicate * a predicate function to evaluate items emitted by the source Observable * @return an Observable that emits the single item emitted by the source Observable that matches the * predicate, or the default item if no emitted item matches the predicate * @throws IllegalArgumentException * if the source Observable emits more than one item that matches the predicate * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> singleOrDefault(T defaultValue, Func1<? super T, Boolean> predicate) { return filter(predicate).singleOrDefault(defaultValue); } /** * Returns an Observable that skips the first {@code num} items emitted by the source Observable and emits * the remainder. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/skip.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code skip} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param num * the number of items to skip * @return an Observable that is identical to the source Observable except that it does not emit the first * {@code num} items that the source Observable emits * @see <a href="http://reactivex.io/documentation/operators/skip.html">ReactiveX operators documentation: Skip</a> */ public final Observable<T> skip(int num) { return lift(new OperatorSkip<T>(num)); } /** * Returns an Observable that skips values emitted by the source Observable before a specified time window * elapses. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/skip.t.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code skip} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param time * the length of the time window to skip * @param unit * the time unit of {@code time} * @return an Observable that skips values emitted by the source Observable before the time window defined * by {@code time} elapses and the emits the remainder * @see <a href="http://reactivex.io/documentation/operators/skip.html">ReactiveX operators documentation: Skip</a> */ public final Observable<T> skip(long time, TimeUnit unit) { return skip(time, unit, Schedulers.computation()); } /** * Returns an Observable that skips values emitted by the source Observable before a specified time window * on a specified {@link Scheduler} elapses. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/skip.ts.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param time * the length of the time window to skip * @param unit * the time unit of {@code time} * @param scheduler * the {@link Scheduler} on which the timed wait happens * @return an Observable that skips values emitted by the source Observable before the time window defined * by {@code time} and {@code scheduler} elapses, and then emits the remainder * @see <a href="http://reactivex.io/documentation/operators/skip.html">ReactiveX operators documentation: Skip</a> */ public final Observable<T> skip(long time, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorSkipTimed<T>(time, unit, scheduler)); } /** * Returns an Observable that drops a specified number of items from the end of the sequence emitted by the * source Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/skipLast.png" alt=""> * <p> * This Observer accumulates a queue long enough to store the first {@code count} items. As more items are * received, items are taken from the front of the queue and emitted by the returned Observable. This causes * such items to be delayed. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code skipLast} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param count * number of items to drop from the end of the source sequence * @return an Observable that emits the items emitted by the source Observable except for the dropped ones * at the end * @throws IndexOutOfBoundsException * if {@code count} is less than zero * @see <a href="http://reactivex.io/documentation/operators/skiplast.html">ReactiveX operators documentation: SkipLast</a> */ public final Observable<T> skipLast(int count) { return lift(new OperatorSkipLast<T>(count)); } /** * Returns an Observable that drops items emitted by the source Observable during a specified time window * before the source completes. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/skipLast.t.png" alt=""> * <p> * Note: this action will cache the latest items arriving in the specified time window. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code skipLast} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param time * the length of the time window * @param unit * the time unit of {@code time} * @return an Observable that drops those items emitted by the source Observable in a time window before the * source completes defined by {@code time} * @see <a href="http://reactivex.io/documentation/operators/skiplast.html">ReactiveX operators documentation: SkipLast</a> */ public final Observable<T> skipLast(long time, TimeUnit unit) { return skipLast(time, unit, Schedulers.computation()); } /** * Returns an Observable that drops items emitted by the source Observable during a specified time window * (defined on a specified scheduler) before the source completes. * <p> * <img width="640" height="340" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/skipLast.ts.png" alt=""> * <p> * Note: this action will cache the latest items arriving in the specified time window. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param time * the length of the time window * @param unit * the time unit of {@code time} * @param scheduler * the scheduler used as the time source * @return an Observable that drops those items emitted by the source Observable in a time window before the * source completes defined by {@code time} and {@code scheduler} * @see <a href="http://reactivex.io/documentation/operators/skiplast.html">ReactiveX operators documentation: SkipLast</a> */ public final Observable<T> skipLast(long time, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorSkipLastTimed<T>(time, unit, scheduler)); } /** * Returns an Observable that skips items emitted by the source Observable until a second Observable emits * an item. * <p> * <img width="640" height="375" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/skipUntil.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code skipUntil} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param other * the second Observable that has to emit an item before the source Observable's elements begin * to be mirrored by the resulting Observable * @return an Observable that skips items from the source Observable until the second Observable emits an * item, then emits the remaining items * @see <a href="http://reactivex.io/documentation/operators/skipuntil.html">ReactiveX operators documentation: SkipUntil</a> */ public final <U> Observable<T> skipUntil(Observable<U> other) { return lift(new OperatorSkipUntil<T, U>(other)); } /** * Returns an Observable that skips all items emitted by the source Observable as long as a specified * condition holds true, but emits all further source items as soon as the condition becomes false. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/skipWhile.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code skipWhile} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * a function to test each item emitted from the source Observable * @return an Observable that begins emitting items emitted by the source Observable when the specified * predicate becomes false * @see <a href="http://reactivex.io/documentation/operators/skipwhile.html">ReactiveX operators documentation: SkipWhile</a> */ public final Observable<T> skipWhile(Func1<? super T, Boolean> predicate) { return lift(new OperatorSkipWhile<T>(OperatorSkipWhile.toPredicate2(predicate))); } /** * Returns an Observable that emits the items in a specified {@link Observable} before it begins to emit * items emitted by the source Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.o.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param values * an Observable that contains the items you want the modified Observable to emit first * @return an Observable that emits the items in the specified {@link Observable} and then emits the items * emitted by the source Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(Observable<T> values) { return concat(values, this); } /** * Returns an Observable that emits the items in a specified {@link Iterable} before it begins to emit items * emitted by the source Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param values * an Iterable that contains the items you want the modified Observable to emit first * @return an Observable that emits the items in the specified {@link Iterable} and then emits the items * emitted by the source Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(Iterable<T> values) { return concat(Observable.<T> from(values), this); } /** * Returns an Observable that emits a specified item before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the item to emit * @return an Observable that emits the specified item before it begins to emit items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1) { return concat(just(t1), this); } /** * Returns an Observable that emits the specified items before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the first item to emit * @param t2 * the second item to emit * @return an Observable that emits the specified items before it begins to emit items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1, T t2) { return concat(just(t1, t2), this); } /** * Returns an Observable that emits the specified items before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the first item to emit * @param t2 * the second item to emit * @param t3 * the third item to emit * @return an Observable that emits the specified items before it begins to emit items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1, T t2, T t3) { return concat(just(t1, t2, t3), this); } /** * Returns an Observable that emits the specified items before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the first item to emit * @param t2 * the second item to emit * @param t3 * the third item to emit * @param t4 * the fourth item to emit * @return an Observable that emits the specified items before it begins to emit items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1, T t2, T t3, T t4) { return concat(just(t1, t2, t3, t4), this); } /** * Returns an Observable that emits the specified items before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the first item to emit * @param t2 * the second item to emit * @param t3 * the third item to emit * @param t4 * the fourth item to emit * @param t5 * the fifth item to emit * @return an Observable that emits the specified items before it begins to emit items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1, T t2, T t3, T t4, T t5) { return concat(just(t1, t2, t3, t4, t5), this); } /** * Returns an Observable that emits the specified items before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the first item to emit * @param t2 * the second item to emit * @param t3 * the third item to emit * @param t4 * the fourth item to emit * @param t5 * the fifth item to emit * @param t6 * the sixth item to emit * @return an Observable that emits the specified items before it begins to emit items emitted * by the source Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1, T t2, T t3, T t4, T t5, T t6) { return concat(just(t1, t2, t3, t4, t5, t6), this); } /** * Returns an Observable that emits the specified items before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the first item to emit * @param t2 * the second item to emit * @param t3 * the third item to emit * @param t4 * the fourth item to emit * @param t5 * the fifth item to emit * @param t6 * the sixth item to emit * @param t7 * the seventh item to emit * @return an Observable that emits the specified items before it begins to emit items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1, T t2, T t3, T t4, T t5, T t6, T t7) { return concat(just(t1, t2, t3, t4, t5, t6, t7), this); } /** * Returns an Observable that emits the specified items before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the first item to emit * @param t2 * the second item to emit * @param t3 * the third item to emit * @param t4 * the fourth item to emit * @param t5 * the fifth item to emit * @param t6 * the sixth item to emit * @param t7 * the seventh item to emit * @param t8 * the eighth item to emit * @return an Observable that emits the specified items before it begins to emit items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1, T t2, T t3, T t4, T t5, T t6, T t7, T t8) { return concat(just(t1, t2, t3, t4, t5, t6, t7, t8), this); } /** * Returns an Observable that emits the specified items before it begins to emit items emitted by the source * Observable. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/startWith.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code startWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param t1 * the first item to emit * @param t2 * the second item to emit * @param t3 * the third item to emit * @param t4 * the fourth item to emit * @param t5 * the fifth item to emit * @param t6 * the sixth item to emit * @param t7 * the seventh item to emit * @param t8 * the eighth item to emit * @param t9 * the ninth item to emit * @return an Observable that emits the specified items before it begins to emit items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/startwith.html">ReactiveX operators documentation: StartWith</a> */ public final Observable<T> startWith(T t1, T t2, T t3, T t4, T t5, T t6, T t7, T t8, T t9) { return concat(just(t1, t2, t3, t4, t5, t6, t7, t8, t9), this); } /** * Subscribes to an Observable but ignore its emissions and notifications. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code subscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return a {@link Subscription} reference with which the {@link Observer} can stop receiving items before * the Observable has finished sending them * @throws OnErrorNotImplementedException * if the Observable tries to call {@code onError} * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> */ public final Subscription subscribe() { return subscribe(new Subscriber<T>() { @Override public final void onCompleted() { // do nothing } @Override public final void onError(Throwable e) { throw new OnErrorNotImplementedException(e); } @Override public final void onNext(T args) { // do nothing } }); } /** * Subscribes to an Observable and provides a callback to handle the items it emits. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code subscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onNext * the {@code Action1<T>} you have designed to accept emissions from the Observable * @return a {@link Subscription} reference with which the {@link Observer} can stop receiving items before * the Observable has finished sending them * @throws IllegalArgumentException * if {@code onNext} is null * @throws OnErrorNotImplementedException * if the Observable tries to call {@code onError} * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> */ public final Subscription subscribe(final Action1<? super T> onNext) { if (onNext == null) { throw new IllegalArgumentException("onNext can not be null"); } return subscribe(new Subscriber<T>() { @Override public final void onCompleted() { // do nothing } @Override public final void onError(Throwable e) { throw new OnErrorNotImplementedException(e); } @Override public final void onNext(T args) { onNext.call(args); } }); } /** * Subscribes to an Observable and provides callbacks to handle the items it emits and any error * notification it issues. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code subscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onNext * the {@code Action1<T>} you have designed to accept emissions from the Observable * @param onError * the {@code Action1<Throwable>} you have designed to accept any error notification from the * Observable * @return a {@link Subscription} reference with which the {@link Observer} can stop receiving items before * the Observable has finished sending them * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> * @throws IllegalArgumentException * if {@code onNext} is null, or * if {@code onError} is null */ public final Subscription subscribe(final Action1<? super T> onNext, final Action1<Throwable> onError) { if (onNext == null) { throw new IllegalArgumentException("onNext can not be null"); } if (onError == null) { throw new IllegalArgumentException("onError can not be null"); } return subscribe(new Subscriber<T>() { @Override public final void onCompleted() { // do nothing } @Override public final void onError(Throwable e) { onError.call(e); } @Override public final void onNext(T args) { onNext.call(args); } }); } /** * Subscribes to an Observable and provides callbacks to handle the items it emits and any error or * completion notification it issues. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code subscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param onNext * the {@code Action1<T>} you have designed to accept emissions from the Observable * @param onError * the {@code Action1<Throwable>} you have designed to accept any error notification from the * Observable * @param onComplete * the {@code Action0} you have designed to accept a completion notification from the * Observable * @return a {@link Subscription} reference with which the {@link Observer} can stop receiving items before * the Observable has finished sending them * @throws IllegalArgumentException * if {@code onNext} is null, or * if {@code onError} is null, or * if {@code onComplete} is null * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> */ public final Subscription subscribe(final Action1<? super T> onNext, final Action1<Throwable> onError, final Action0 onComplete) { if (onNext == null) { throw new IllegalArgumentException("onNext can not be null"); } if (onError == null) { throw new IllegalArgumentException("onError can not be null"); } if (onComplete == null) { throw new IllegalArgumentException("onComplete can not be null"); } return subscribe(new Subscriber<T>() { @Override public final void onCompleted() { onComplete.call(); } @Override public final void onError(Throwable e) { onError.call(e); } @Override public final void onNext(T args) { onNext.call(args); } }); } /** * Subscribes to an Observable and provides an Observer that implements functions to handle the items the * Observable emits and any error or completion notification it issues. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code subscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param observer * the Observer that will handle emissions and notifications from the Observable * @return a {@link Subscription} reference with which the {@link Observer} can stop receiving items before * the Observable has completed * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> */ public final Subscription subscribe(final Observer<? super T> observer) { if (observer instanceof Subscriber) { return subscribe((Subscriber<? super T>)observer); } return subscribe(new Subscriber<T>() { @Override public void onCompleted() { observer.onCompleted(); } @Override public void onError(Throwable e) { observer.onError(e); } @Override public void onNext(T t) { observer.onNext(t); } }); } /** * Subscribes to an Observable and invokes {@link OnSubscribe} function without any contract protection, * error handling, unsubscribe, or execution hooks. * <p> * Use this only for implementing an {@link Operator} that requires nested subscriptions. For other * purposes, use {@link #subscribe(Subscriber)} which ensures the Rx contract and other functionality. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code unsafeSubscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param subscriber * the Subscriber that will handle emissions and notifications from the Observable * @return a {@link Subscription} reference with which the {@link Subscriber} can stop receiving items * before the Observable has completed */ public final Subscription unsafeSubscribe(Subscriber<? super T> subscriber) { try { // new Subscriber so onStart it subscriber.onStart(); // allow the hook to intercept and/or decorate hook.onSubscribeStart(this, onSubscribe).call(subscriber); return hook.onSubscribeReturn(subscriber); } catch (Throwable e) { // special handling for certain Throwable/Error/Exception types Exceptions.throwIfFatal(e); // if an unhandled error occurs executing the onSubscribe we will propagate it try { subscriber.onError(hook.onSubscribeError(e)); } catch (OnErrorNotImplementedException e2) { // special handling when onError is not implemented ... we just rethrow throw e2; } catch (Throwable e2) { // if this happens it means the onError itself failed (perhaps an invalid function implementation) // so we are unable to propagate the error correctly and will just throw RuntimeException r = new RuntimeException("Error occurred attempting to subscribe [" + e.getMessage() + "] and then again while trying to pass to onError.", e2); // TODO could the hook be the cause of the error in the on error handling. hook.onSubscribeError(r); // TODO why aren't we throwing the hook's return value. throw r; } return Subscriptions.unsubscribed(); } } /** * Subscribes to an Observable and provides a Subscriber that implements functions to handle the items the * Observable emits and any error or completion notification it issues. * <p> * A typical implementation of {@code subscribe} does the following: * <ol> * <li>It stores a reference to the Subscriber in a collection object, such as a {@code List<T>} object.</li> * <li>It returns a reference to the {@link Subscription} interface. This enables Subscribers to * unsubscribe, that is, to stop receiving items and notifications before the Observable completes, which * also invokes the Subscriber's {@link Subscriber#onCompleted onCompleted} method.</li> * </ol><p> * An {@code Observable<T>} instance is responsible for accepting all subscriptions and notifying all * Subscribers. Unless the documentation for a particular {@code Observable<T>} implementation indicates * otherwise, Subscriber should make no assumptions about the order in which multiple Subscribers will * receive their notifications. * <p> * For more information see the * <a href="http://reactivex.io/documentation/observable.html">ReactiveX documentation</a>. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code subscribe} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param subscriber * the {@link Subscriber} that will handle emissions and notifications from the Observable * @return a {@link Subscription} reference with which Subscribers that are {@link Observer}s can * unsubscribe from the Observable * @throws IllegalStateException * if {@code subscribe} is unable to obtain an {@code OnSubscribe<>} function * @throws IllegalArgumentException * if the {@link Subscriber} provided as the argument to {@code subscribe} is {@code null} * @throws OnErrorNotImplementedException * if the {@link Subscriber}'s {@code onError} method is null * @throws RuntimeException * if the {@link Subscriber}'s {@code onError} method itself threw a {@code Throwable} * @see <a href="http://reactivex.io/documentation/operators/subscribe.html">ReactiveX operators documentation: Subscribe</a> */ public final Subscription subscribe(Subscriber<? super T> subscriber) { // validate and proceed if (subscriber == null) { throw new IllegalArgumentException("observer can not be null"); } if (onSubscribe == null) { throw new IllegalStateException("onSubscribe function can not be null."); /* * the subscribe function can also be overridden but generally that's not the appropriate approach * so I won't mention that in the exception */ } // new Subscriber so onStart it subscriber.onStart(); /* * See https://github.com/ReactiveX/RxJava/issues/216 for discussion on "Guideline 6.4: Protect calls * to user code from within an Observer" */ // if not already wrapped if (!(subscriber instanceof SafeSubscriber)) { // assign to `observer` so we return the protected version subscriber = new SafeSubscriber<T>(subscriber); } // The code below is exactly the same an unsafeSubscribe but not used because it would add a sigificent depth to alreay huge call stacks. try { // allow the hook to intercept and/or decorate hook.onSubscribeStart(this, onSubscribe).call(subscriber); return hook.onSubscribeReturn(subscriber); } catch (Throwable e) { // special handling for certain Throwable/Error/Exception types Exceptions.throwIfFatal(e); // if an unhandled error occurs executing the onSubscribe we will propagate it try { subscriber.onError(hook.onSubscribeError(e)); } catch (OnErrorNotImplementedException e2) { // special handling when onError is not implemented ... we just rethrow throw e2; } catch (Throwable e2) { // if this happens it means the onError itself failed (perhaps an invalid function implementation) // so we are unable to propagate the error correctly and will just throw RuntimeException r = new RuntimeException("Error occurred attempting to subscribe [" + e.getMessage() + "] and then again while trying to pass to onError.", e2); // TODO could the hook be the cause of the error in the on error handling. hook.onSubscribeError(r); // TODO why aren't we throwing the hook's return value. throw r; } return Subscriptions.unsubscribed(); } } /** * Asynchronously subscribes Observers to this Observable on the specified {@link Scheduler}. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/subscribeOn.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param scheduler * the {@link Scheduler} to perform subscription actions on * @return the source Observable modified so that its subscriptions happen on the * specified {@link Scheduler} * @see <a href="http://reactivex.io/documentation/operators/subscribeon.html">ReactiveX operators documentation: SubscribeOn</a> * @see <a href="http://www.grahamlea.com/2014/07/rxjava-threading-examples/">RxJava Threading Examples</a> * @see #observeOn */ public final Observable<T> subscribeOn(Scheduler scheduler) { if (this instanceof ScalarSynchronousObservable) { return ((ScalarSynchronousObservable<T>)this).scalarScheduleOn(scheduler); } return nest().lift(new OperatorSubscribeOn<T>(scheduler)); } /** * Returns a new Observable by applying a function that you supply to each item emitted by the source * Observable that returns an Observable, and then emitting the items emitted by the most recently emitted * of these Observables. * <p> * <img width="640" height="350" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/switchMap.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code switchMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param func * a function that, when applied to an item emitted by the source Observable, returns an * Observable * @return an Observable that emits the items emitted by the Observable returned from applying {@code func} to the most recently emitted item emitted by the source Observable * @see <a href="http://reactivex.io/documentation/operators/flatmap.html">ReactiveX operators documentation: FlatMap</a> */ public final <R> Observable<R> switchMap(Func1<? super T, ? extends Observable<? extends R>> func) { return switchOnNext(map(func)); } /** * Returns an Observable that emits only the first {@code num} items emitted by the source Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/take.png" alt=""> * <p> * This method returns an Observable that will invoke a subscribing {@link Observer}'s * {@link Observer#onNext onNext} function a maximum of {@code num} times before invoking * {@link Observer#onCompleted onCompleted}. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code take} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param num * the maximum number of items to emit * @return an Observable that emits only the first {@code num} items emitted by the source Observable, or * all of the items from the source Observable if that Observable emits fewer than {@code num} items * @see <a href="http://reactivex.io/documentation/operators/take.html">ReactiveX operators documentation: Take</a> */ public final Observable<T> take(final int num) { return lift(new OperatorTake<T>(num)); } /** * Returns an Observable that emits those items emitted by source Observable before a specified time runs * out. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/take.t.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code take} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param time * the length of the time window * @param unit * the time unit of {@code time} * @return an Observable that emits those items emitted by the source Observable before the time runs out * @see <a href="http://reactivex.io/documentation/operators/take.html">ReactiveX operators documentation: Take</a> */ public final Observable<T> take(long time, TimeUnit unit) { return take(time, unit, Schedulers.computation()); } /** * Returns an Observable that emits those items emitted by source Observable before a specified time (on a * specified Scheduler) runs out. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/take.ts.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param time * the length of the time window * @param unit * the time unit of {@code time} * @param scheduler * the Scheduler used for time source * @return an Observable that emits those items emitted by the source Observable before the time runs out, * according to the specified Scheduler * @see <a href="http://reactivex.io/documentation/operators/take.html">ReactiveX operators documentation: Take</a> */ public final Observable<T> take(long time, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorTakeTimed<T>(time, unit, scheduler)); } /** * Returns an Observable that emits only the very first item emitted by the source Observable that satisfies * a specified condition. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeFirstN.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code takeFirst} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * the condition any item emitted by the source Observable has to satisfy * @return an Observable that emits only the very first item emitted by the source Observable that satisfies * the given condition, or that completes without emitting anything if the source Observable * completes without emitting a single condition-satisfying item * @see <a href="http://reactivex.io/documentation/operators/first.html">ReactiveX operators documentation: First</a> */ public final Observable<T> takeFirst(Func1<? super T, Boolean> predicate) { return filter(predicate).take(1); } /** * Returns an Observable that emits only the last {@code count} items emitted by the source Observable. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLast.n.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code takeLast} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param count * the number of items to emit from the end of the sequence of items emitted by the source * Observable * @return an Observable that emits only the last {@code count} items emitted by the source Observable * @throws IndexOutOfBoundsException * if {@code count} is less than zero * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<T> takeLast(final int count) { return lift(new OperatorTakeLast<T>(count)); } /** * Returns an Observable that emits at most a specified number of items from the source Observable that were * emitted in a specified window of time before the Observable completed. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLast.tn.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code takeLast} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param count * the maximum number of items to emit * @param time * the length of the time window * @param unit * the time unit of {@code time} * @return an Observable that emits at most {@code count} items from the source Observable that were emitted * in a specified window of time before the Observable completed * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<T> takeLast(int count, long time, TimeUnit unit) { return takeLast(count, time, unit, Schedulers.computation()); } /** * Returns an Observable that emits at most a specified number of items from the source Observable that were * emitted in a specified window of time before the Observable completed, where the timing information is * provided by a given Scheduler. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLast.tns.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param count * the maximum number of items to emit * @param time * the length of the time window * @param unit * the time unit of {@code time} * @param scheduler * the {@link Scheduler} that provides the timestamps for the observed items * @return an Observable that emits at most {@code count} items from the source Observable that were emitted * in a specified window of time before the Observable completed, where the timing information is * provided by the given {@code scheduler} * @throws IndexOutOfBoundsException * if {@code count} is less than zero * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<T> takeLast(int count, long time, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorTakeLastTimed<T>(count, time, unit, scheduler)); } /** * Returns an Observable that emits the items from the source Observable that were emitted in a specified * window of time before the Observable completed. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLast.t.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code takeLast} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param time * the length of the time window * @param unit * the time unit of {@code time} * @return an Observable that emits the items from the source Observable that were emitted in the window of * time before the Observable completed specified by {@code time} * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<T> takeLast(long time, TimeUnit unit) { return takeLast(time, unit, Schedulers.computation()); } /** * Returns an Observable that emits the items from the source Observable that were emitted in a specified * window of time before the Observable completed, where the timing information is provided by a specified * Scheduler. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLast.ts.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param time * the length of the time window * @param unit * the time unit of {@code time} * @param scheduler * the Scheduler that provides the timestamps for the Observed items * @return an Observable that emits the items from the source Observable that were emitted in the window of * time before the Observable completed specified by {@code time}, where the timing information is * provided by {@code scheduler} * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<T> takeLast(long time, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorTakeLastTimed<T>(time, unit, scheduler)); } /** * Returns an Observable that emits a single List containing the last {@code count} elements emitted by the * source Observable. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLastBuffer.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code takeLastBuffer} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param count * the number of items to emit in the list * @return an Observable that emits a single list containing the last {@code count} elements emitted by the * source Observable * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<List<T>> takeLastBuffer(int count) { return takeLast(count).toList(); } /** * Returns an Observable that emits a single List containing at most {@code count} items from the source * Observable that were emitted during a specified window of time before the source Observable completed. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLastBuffer.tn.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code takeLastBuffer} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param count * the maximum number of items to emit * @param time * the length of the time window * @param unit * the time unit of {@code time} * @return an Observable that emits a single List containing at most {@code count} items emitted by the * source Observable during the time window defined by {@code time} before the source Observable * completed * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<List<T>> takeLastBuffer(int count, long time, TimeUnit unit) { return takeLast(count, time, unit).toList(); } /** * Returns an Observable that emits a single List containing at most {@code count} items from the source * Observable that were emitted during a specified window of time (on a specified Scheduler) before the * source Observable completed. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLastBuffer.tns.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param count * the maximum number of items to emit * @param time * the length of the time window * @param unit * the time unit of {@code time} * @param scheduler * the Scheduler that provides the timestamps for the observed items * @return an Observable that emits a single List containing at most {@code count} items emitted by the * source Observable during the time window defined by {@code time} before the source Observable * completed * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<List<T>> takeLastBuffer(int count, long time, TimeUnit unit, Scheduler scheduler) { return takeLast(count, time, unit, scheduler).toList(); } /** * Returns an Observable that emits a single List containing those items from the source Observable that * were emitted during a specified window of time before the source Observable completed. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLastBuffer.t.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code takeLastBuffer} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param time * the length of the time window * @param unit * the time unit of {@code time} * @return an Observable that emits a single List containing the items emitted by the source Observable * during the time window defined by {@code time} before the source Observable completed * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<List<T>> takeLastBuffer(long time, TimeUnit unit) { return takeLast(time, unit).toList(); } /** * Returns an Observable that emits a single List containing those items from the source Observable that * were emitted during a specified window of time before the source Observable completed, where the timing * information is provided by the given Scheduler. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeLastBuffer.ts.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param time * the length of the time window * @param unit * the time unit of {@code time} * @param scheduler * the Scheduler that provides the timestamps for the observed items * @return an Observable that emits a single List containing the items emitted by the source Observable * during the time window defined by {@code time} before the source Observable completed, where the * timing information is provided by {@code scheduler} * @see <a href="http://reactivex.io/documentation/operators/takelast.html">ReactiveX operators documentation: TakeLast</a> */ public final Observable<List<T>> takeLastBuffer(long time, TimeUnit unit, Scheduler scheduler) { return takeLast(time, unit, scheduler).toList(); } /** * Returns an Observable that emits the items emitted by the source Observable until a second Observable * emits an item. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeUntil.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code takeUntil} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param other * the Observable whose first emitted item will cause {@code takeUntil} to stop emitting items * from the source Observable * @param <E> * the type of items emitted by {@code other} * @return an Observable that emits the items emitted by the source Observable until such time as {@code other} emits its first item * @see <a href="http://reactivex.io/documentation/operators/takeuntil.html">ReactiveX operators documentation: TakeUntil</a> */ public final <E> Observable<T> takeUntil(Observable<? extends E> other) { return lift(new OperatorTakeUntil<T, E>(other)); } /** * Returns an Observable that emits items emitted by the source Observable so long as each item satisfied a * specified condition, and then completes as soon as this condition is not satisfied. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeWhile.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code takeWhile} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param predicate * a function that evaluates an item emitted by the source Observable and returns a Boolean * @return an Observable that emits the items from the source Observable so long as each item satisfies the * condition defined by {@code predicate}, then completes * @see <a href="http://reactivex.io/documentation/operators/takewhile.html">ReactiveX operators documentation: TakeWhile</a> * @see Observable#takeUntil(Func1) */ public final Observable<T> takeWhile(final Func1<? super T, Boolean> predicate) { return lift(new OperatorTakeWhile<T>(predicate)); } /** * Returns an Observable that emits items emitted by the source Observable, checks the specified predicate * for each item, and then completes if the condition is satisfied. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/takeUntil.p.png" alt=""> * <p> * The difference between this operator and {@link #takeWhile(Func1)} is that here, the condition is * evaluated <em>after</em> the item is emitted. * * @warn "Scheduler" and "Backpressure Support" sections missing from javadocs * @param stopPredicate * a function that evaluates an item emitted by the source Observable and returns a Boolean * @return an Observable that first emits items emitted by the source Observable, checks the specified * condition after each item, and then completes if the condition is satisfied. * @see <a href="http://reactivex.io/documentation/operators/takeuntil.html">ReactiveX operators documentation: TakeUntil</a> * @see Observable#takeWhile(Func1) * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) */ @Experimental public final Observable<T> takeUntil(final Func1<? super T, Boolean> stopPredicate) { return lift(new OperatorTakeUntilPredicate<T>(stopPredicate)); } /** * Returns an Observable that emits only the first item emitted by the source Observable during sequential * time windows of a specified duration. * <p> * This differs from {@link #throttleLast} in that this only tracks passage of time whereas * {@link #throttleLast} ticks at scheduled intervals. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/throttleFirst.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code throttleFirst} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param windowDuration * time to wait before emitting another item after emitting the last item * @param unit * the unit of time of {@code windowDuration} * @return an Observable that performs the throttle operation * @see <a href="http://reactivex.io/documentation/operators/sample.html">ReactiveX operators documentation: Sample</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> */ public final Observable<T> throttleFirst(long windowDuration, TimeUnit unit) { return throttleFirst(windowDuration, unit, Schedulers.computation()); } /** * Returns an Observable that emits only the first item emitted by the source Observable during sequential * time windows of a specified duration, where the windows are managed by a specified Scheduler. * <p> * This differs from {@link #throttleLast} in that this only tracks passage of time whereas * {@link #throttleLast} ticks at scheduled intervals. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/throttleFirst.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param skipDuration * time to wait before emitting another item after emitting the last item * @param unit * the unit of time of {@code skipDuration} * @param scheduler * the {@link Scheduler} to use internally to manage the timers that handle timeout for each * event * @return an Observable that performs the throttle operation * @see <a href="http://reactivex.io/documentation/operators/sample.html">ReactiveX operators documentation: Sample</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> */ public final Observable<T> throttleFirst(long skipDuration, TimeUnit unit, Scheduler scheduler) { return lift(new OperatorThrottleFirst<T>(skipDuration, unit, scheduler)); } /** * Returns an Observable that emits only the last item emitted by the source Observable during sequential * time windows of a specified duration. * <p> * This differs from {@link #throttleFirst} in that this ticks along at a scheduled interval whereas * {@link #throttleFirst} does not tick, it just tracks passage of time. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/throttleLast.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code throttleLast} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param intervalDuration * duration of windows within which the last item emitted by the source Observable will be * emitted * @param unit * the unit of time of {@code intervalDuration} * @return an Observable that performs the throttle operation * @see <a href="http://reactivex.io/documentation/operators/sample.html">ReactiveX operators documentation: Sample</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> * @see #sample(long, TimeUnit) */ public final Observable<T> throttleLast(long intervalDuration, TimeUnit unit) { return sample(intervalDuration, unit); } /** * Returns an Observable that emits only the last item emitted by the source Observable during sequential * time windows of a specified duration, where the duration is governed by a specified Scheduler. * <p> * This differs from {@link #throttleFirst} in that this ticks along at a scheduled interval whereas * {@link #throttleFirst} does not tick, it just tracks passage of time. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/throttleLast.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param intervalDuration * duration of windows within which the last item emitted by the source Observable will be * emitted * @param unit * the unit of time of {@code intervalDuration} * @param scheduler * the {@link Scheduler} to use internally to manage the timers that handle timeout for each * event * @return an Observable that performs the throttle operation * @see <a href="http://reactivex.io/documentation/operators/sample.html">ReactiveX operators documentation: Sample</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> * @see #sample(long, TimeUnit, Scheduler) */ public final Observable<T> throttleLast(long intervalDuration, TimeUnit unit, Scheduler scheduler) { return sample(intervalDuration, unit, scheduler); } /** * Returns an Observable that only emits those items emitted by the source Observable that are not followed * by another emitted item within a specified time window. * <p> * <em>Note:</em> If the source Observable keeps emitting items more frequently than the length of the time * window then no items will be emitted by the resulting Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/throttleWithTimeout.png" alt=""> * <p> * Information on debounce vs throttle: * <p> * <ul> * <li><a href="http://drupalmotion.com/article/debounce-and-throttle-visual-explanation">Debounce and Throttle: visual explanation</a></li> * <li><a href="http://unscriptable.com/2009/03/20/debouncing-javascript-methods/">Debouncing: javascript methods</a></li> * <li><a href="http://www.illyriad.co.uk/blog/index.php/2011/09/javascript-dont-spam-your-server-debounce-and-throttle/">Javascript - don't spam your server: debounce and throttle</a></li> * </ul> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code throttleWithTimeout} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timeout * the length of the window of time that must pass after the emission of an item from the source * Observable in which that Observable emits no items in order for the item to be emitted by the * resulting Observable * @param unit * the {@link TimeUnit} of {@code timeout} * @return an Observable that filters out items that are too quickly followed by newer items * @see <a href="http://reactivex.io/documentation/operators/debounce.html">ReactiveX operators documentation: Debounce</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> * @see #debounce(long, TimeUnit) */ public final Observable<T> throttleWithTimeout(long timeout, TimeUnit unit) { return debounce(timeout, unit); } /** * Returns an Observable that only emits those items emitted by the source Observable that are not followed * by another emitted item within a specified time window, where the time window is governed by a specified * Scheduler. * <p> * <em>Note:</em> If the source Observable keeps emitting items more frequently than the length of the time * window then no items will be emitted by the resulting Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/throttleWithTimeout.s.png" alt=""> * <p> * Information on debounce vs throttle: * <p> * <ul> * <li><a href="http://drupalmotion.com/article/debounce-and-throttle-visual-explanation">Debounce and Throttle: visual explanation</a></li> * <li><a href="http://unscriptable.com/2009/03/20/debouncing-javascript-methods/">Debouncing: javascript methods</a></li> * <li><a href="http://www.illyriad.co.uk/blog/index.php/2011/09/javascript-dont-spam-your-server-debounce-and-throttle/">Javascript - don't spam your server: debounce and throttle</a></li> * </ul> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timeout * the length of the window of time that must pass after the emission of an item from the source * Observable in which that Observable emits no items in order for the item to be emitted by the * resulting Observable * @param unit * the {@link TimeUnit} of {@code timeout} * @param scheduler * the {@link Scheduler} to use internally to manage the timers that handle the timeout for each * item * @return an Observable that filters out items that are too quickly followed by newer items * @see <a href="http://reactivex.io/documentation/operators/debounce.html">ReactiveX operators documentation: Debounce</a> * @see <a href="https://github.com/ReactiveX/RxJava/wiki/Backpressure">RxJava wiki: Backpressure</a> * @see #debounce(long, TimeUnit, Scheduler) */ public final Observable<T> throttleWithTimeout(long timeout, TimeUnit unit, Scheduler scheduler) { return debounce(timeout, unit, scheduler); } /** * Returns an Observable that emits records of the time interval between consecutive items emitted by the * source Observable. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeInterval.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code timeInterval} operates by default on the {@code immediate} {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits time interval information items * @see <a href="http://reactivex.io/documentation/operators/timeinterval.html">ReactiveX operators documentation: TimeInterval</a> */ public final Observable<TimeInterval<T>> timeInterval() { return timeInterval(Schedulers.immediate()); } /** * Returns an Observable that emits records of the time interval between consecutive items emitted by the * source Observable, where this interval is computed on a specified Scheduler. * <p> * <img width="640" height="315" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeInterval.s.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param scheduler * the {@link Scheduler} used to compute time intervals * @return an Observable that emits time interval information items * @see <a href="http://reactivex.io/documentation/operators/timeinterval.html">ReactiveX operators documentation: TimeInterval</a> */ public final Observable<TimeInterval<T>> timeInterval(Scheduler scheduler) { return lift(new OperatorTimeInterval<T>(scheduler)); } /** * Returns an Observable that mirrors the source Observable, but notifies observers of a * {@code TimeoutException} if either the first item emitted by the source Observable or any subsequent item * doesn't arrive within time windows defined by other Observables. * <p> * <img width="640" height="400" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeout5.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code timeout} operates by default on the {@code immediate} {@link Scheduler}.</dd> * </dl> * * @param <U> * the first timeout value type (ignored) * @param <V> * the subsequent timeout value type (ignored) * @param firstTimeoutSelector * a function that returns an Observable that determines the timeout window for the first source * item * @param timeoutSelector * a function that returns an Observable for each item emitted by the source Observable and that * determines the timeout window in which the subsequent source item must arrive in order to * continue the sequence * @return an Observable that mirrors the source Observable, but notifies observers of a * {@code TimeoutException} if either the first item or any subsequent item doesn't arrive within * the time windows specified by the timeout selectors * @see <a href="http://reactivex.io/documentation/operators/timeout.html">ReactiveX operators documentation: Timeout</a> */ public final <U, V> Observable<T> timeout(Func0<? extends Observable<U>> firstTimeoutSelector, Func1<? super T, ? extends Observable<V>> timeoutSelector) { return timeout(firstTimeoutSelector, timeoutSelector, null); } /** * Returns an Observable that mirrors the source Observable, but switches to a fallback Observable if either * the first item emitted by the source Observable or any subsequent item doesn't arrive within time windows * defined by other Observables. * <p> * <img width="640" height="400" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeout6.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code timeout} operates by default on the {@code immediate} {@link Scheduler}.</dd> * </dl> * * @param <U> * the first timeout value type (ignored) * @param <V> * the subsequent timeout value type (ignored) * @param firstTimeoutSelector * a function that returns an Observable which determines the timeout window for the first source * item * @param timeoutSelector * a function that returns an Observable for each item emitted by the source Observable and that * determines the timeout window in which the subsequent source item must arrive in order to * continue the sequence * @param other * the fallback Observable to switch to if the source Observable times out * @return an Observable that mirrors the source Observable, but switches to the {@code other} Observable if * either the first item emitted by the source Observable or any subsequent item doesn't arrive * within time windows defined by the timeout selectors * @throws NullPointerException * if {@code timeoutSelector} is null * @see <a href="http://reactivex.io/documentation/operators/timeout.html">ReactiveX operators documentation: Timeout</a> */ public final <U, V> Observable<T> timeout(Func0<? extends Observable<U>> firstTimeoutSelector, Func1<? super T, ? extends Observable<V>> timeoutSelector, Observable<? extends T> other) { if (timeoutSelector == null) { throw new NullPointerException("timeoutSelector is null"); } return lift(new OperatorTimeoutWithSelector<T, U, V>(firstTimeoutSelector, timeoutSelector, other)); } /** * Returns an Observable that mirrors the source Observable, but notifies observers of a * {@code TimeoutException} if an item emitted by the source Observable doesn't arrive within a window of * time after the emission of the previous item, where that period of time is measured by an Observable that * is a function of the previous item. * <p> * <img width="640" height="400" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeout3.png" alt=""> * <p> * Note: The arrival of the first source item is never timed out. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code timeout} operates by default on the {@code immediate} {@link Scheduler}.</dd> * </dl> * * @param <V> * the timeout value type (ignored) * @param timeoutSelector * a function that returns an observable for each item emitted by the source * Observable and that determines the timeout window for the subsequent item * @return an Observable that mirrors the source Observable, but notifies observers of a * {@code TimeoutException} if an item emitted by the source Observable takes longer to arrive than * the time window defined by the selector for the previously emitted item * @see <a href="http://reactivex.io/documentation/operators/timeout.html">ReactiveX operators documentation: Timeout</a> */ public final <V> Observable<T> timeout(Func1<? super T, ? extends Observable<V>> timeoutSelector) { return timeout(null, timeoutSelector, null); } /** * Returns an Observable that mirrors the source Observable, but that switches to a fallback Observable if * an item emitted by the source Observable doesn't arrive within a window of time after the emission of the * previous item, where that period of time is measured by an Observable that is a function of the previous * item. * <p> * <img width="640" height="400" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeout4.png" alt=""> * <p> * Note: The arrival of the first source item is never timed out. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code timeout} operates by default on the {@code immediate} {@link Scheduler}.</dd> * </dl> * * @param <V> * the timeout value type (ignored) * @param timeoutSelector * a function that returns an Observable, for each item emitted by the source Observable, that * determines the timeout window for the subsequent item * @param other * the fallback Observable to switch to if the source Observable times out * @return an Observable that mirrors the source Observable, but switches to mirroring a fallback Observable * if an item emitted by the source Observable takes longer to arrive than the time window defined * by the selector for the previously emitted item * @see <a href="http://reactivex.io/documentation/operators/timeout.html">ReactiveX operators documentation: Timeout</a> */ public final <V> Observable<T> timeout(Func1<? super T, ? extends Observable<V>> timeoutSelector, Observable<? extends T> other) { return timeout(null, timeoutSelector, other); } /** * Returns an Observable that mirrors the source Observable but applies a timeout policy for each emitted * item. If the next item isn't emitted within the specified timeout duration starting from its predecessor, * the resulting Observable terminates and notifies observers of a {@code TimeoutException}. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeout.1.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code timeout} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timeout * maximum duration between emitted items before a timeout occurs * @param timeUnit * the unit of time that applies to the {@code timeout} argument. * @return the source Observable modified to notify observers of a {@code TimeoutException} in case of a * timeout * @see <a href="http://reactivex.io/documentation/operators/timeout.html">ReactiveX operators documentation: Timeout</a> */ public final Observable<T> timeout(long timeout, TimeUnit timeUnit) { return timeout(timeout, timeUnit, null, Schedulers.computation()); } /** * Returns an Observable that mirrors the source Observable but applies a timeout policy for each emitted * item. If the next item isn't emitted within the specified timeout duration starting from its predecessor, * the resulting Observable begins instead to mirror a fallback Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeout.2.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code timeout} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timeout * maximum duration between items before a timeout occurs * @param timeUnit * the unit of time that applies to the {@code timeout} argument * @param other * the fallback Observable to use in case of a timeout * @return the source Observable modified to switch to the fallback Observable in case of a timeout * @see <a href="http://reactivex.io/documentation/operators/timeout.html">ReactiveX operators documentation: Timeout</a> */ public final Observable<T> timeout(long timeout, TimeUnit timeUnit, Observable<? extends T> other) { return timeout(timeout, timeUnit, other, Schedulers.computation()); } /** * Returns an Observable that mirrors the source Observable but applies a timeout policy for each emitted * item using a specified Scheduler. If the next item isn't emitted within the specified timeout duration * starting from its predecessor, the resulting Observable begins instead to mirror a fallback Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeout.2s.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timeout * maximum duration between items before a timeout occurs * @param timeUnit * the unit of time that applies to the {@code timeout} argument * @param other * the Observable to use as the fallback in case of a timeout * @param scheduler * the {@link Scheduler} to run the timeout timers on * @return the source Observable modified so that it will switch to the fallback Observable in case of a * timeout * @see <a href="http://reactivex.io/documentation/operators/timeout.html">ReactiveX operators documentation: Timeout</a> */ public final Observable<T> timeout(long timeout, TimeUnit timeUnit, Observable<? extends T> other, Scheduler scheduler) { return lift(new OperatorTimeout<T>(timeout, timeUnit, other, scheduler)); } /** * Returns an Observable that mirrors the source Observable but applies a timeout policy for each emitted * item, where this policy is governed on a specified Scheduler. If the next item isn't emitted within the * specified timeout duration starting from its predecessor, the resulting Observable terminates and * notifies observers of a {@code TimeoutException}. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timeout.1s.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timeout * maximum duration between items before a timeout occurs * @param timeUnit * the unit of time that applies to the {@code timeout} argument * @param scheduler * the Scheduler to run the timeout timers on * @return the source Observable modified to notify observers of a {@code TimeoutException} in case of a * timeout * @see <a href="http://reactivex.io/documentation/operators/timeout.html">ReactiveX operators documentation: Timeout</a> */ public final Observable<T> timeout(long timeout, TimeUnit timeUnit, Scheduler scheduler) { return timeout(timeout, timeUnit, null, scheduler); } /** * Returns an Observable that emits each item emitted by the source Observable, wrapped in a * {@link Timestamped} object. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timestamp.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code timestamp} operates by default on the {@code immediate} {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits timestamped items from the source Observable * @see <a href="http://reactivex.io/documentation/operators/timestamp.html">ReactiveX operators documentation: Timestamp</a> */ public final Observable<Timestamped<T>> timestamp() { return timestamp(Schedulers.immediate()); } /** * Returns an Observable that emits each item emitted by the source Observable, wrapped in a * {@link Timestamped} object whose timestamps are provided by a specified Scheduler. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/timestamp.s.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param scheduler * the {@link Scheduler} to use as a time source * @return an Observable that emits timestamped items from the source Observable with timestamps provided by * the {@code scheduler} * @see <a href="http://reactivex.io/documentation/operators/timestamp.html">ReactiveX operators documentation: Timestamp</a> */ public final Observable<Timestamped<T>> timestamp(Scheduler scheduler) { return lift(new OperatorTimestamp<T>(scheduler)); } /** * Converts an Observable into a {@link BlockingObservable} (an Observable with blocking operators). * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code toBlocking} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return a {@code BlockingObservable} version of this Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final BlockingObservable<T> toBlocking() { return BlockingObservable.from(this); } /** * Returns an Observable that emits a single item, a list composed of all the items emitted by the source * Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toList.png" alt=""> * <p> * Normally, an Observable that returns multiple items will do so by invoking its {@link Observer}'s * {@link Observer#onNext onNext} method for each such item. You can change this behavior, instructing the * Observable to compose a list of all of these items and then to invoke the Observer's {@code onNext} * function once, passing it the entire list, by calling the Observable's {@code toList} method prior to * calling its {@link #subscribe} method. * <p> * Be careful not to use this operator on Observables that emit infinite or very large numbers of items, as * you do not have the option to unsubscribe. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toList} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @return an Observable that emits a single item: a List containing all of the items emitted by the source * Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final Observable<List<T>> toList() { return lift(OperatorToObservableList.<T>instance()); } /** * Returns an Observable that emits a single HashMap containing all items emitted by the source Observable, * mapped by the keys returned by a specified {@code keySelector} function. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toMap.png" alt=""> * <p> * If more than one source item maps to the same key, the HashMap will contain the latest of those items. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * the function that extracts the key from a source item to be used in the HashMap * @return an Observable that emits a single item: a HashMap containing the mapped items from the source * Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final <K> Observable<Map<K, T>> toMap(Func1<? super T, ? extends K> keySelector) { return lift(new OperatorToMap<T, K, T>(keySelector, UtilityFunctions.<T>identity())); } /** * Returns an Observable that emits a single HashMap containing values corresponding to items emitted by the * source Observable, mapped by the keys returned by a specified {@code keySelector} function. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toMap.png" alt=""> * <p> * If more than one source item maps to the same key, the HashMap will contain a single entry that * corresponds to the latest of those items. * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * the function that extracts the key from a source item to be used in the HashMap * @param valueSelector * the function that extracts the value from a source item to be used in the HashMap * @return an Observable that emits a single item: a HashMap containing the mapped items from the source * Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final <K, V> Observable<Map<K, V>> toMap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector) { return lift(new OperatorToMap<T, K, V>(keySelector, valueSelector)); } /** * Returns an Observable that emits a single Map, returned by a specified {@code mapFactory} function, that * contains keys and values extracted from the items emitted by the source Observable. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toMap.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * the function that extracts the key from a source item to be used in the Map * @param valueSelector * the function that extracts the value from the source items to be used as value in the Map * @param mapFactory * the function that returns a Map instance to be used * @return an Observable that emits a single item: a Map that contains the mapped items emitted by the * source Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final <K, V> Observable<Map<K, V>> toMap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector, Func0<? extends Map<K, V>> mapFactory) { return lift(new OperatorToMap<T, K, V>(keySelector, valueSelector, mapFactory)); } /** * Returns an Observable that emits a single HashMap that contains an ArrayList of items emitted by the * source Observable keyed by a specified {@code keySelector} function. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toMultiMap.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toMultiMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * the function that extracts the key from the source items to be used as key in the HashMap * @return an Observable that emits a single item: a HashMap that contains an ArrayList of items mapped from * the source Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final <K> Observable<Map<K, Collection<T>>> toMultimap(Func1<? super T, ? extends K> keySelector) { return lift(new OperatorToMultimap<T, K, T>(keySelector, UtilityFunctions.<T>identity())); } /** * Returns an Observable that emits a single HashMap that contains an ArrayList of values extracted by a * specified {@code valueSelector} function from items emitted by the source Observable, keyed by a * specified {@code keySelector} function. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toMultiMap.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toMultiMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * the function that extracts a key from the source items to be used as key in the HashMap * @param valueSelector * the function that extracts a value from the source items to be used as value in the HashMap * @return an Observable that emits a single item: a HashMap that contains an ArrayList of items mapped from * the source Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final <K, V> Observable<Map<K, Collection<V>>> toMultimap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector) { return lift(new OperatorToMultimap<T, K, V>(keySelector, valueSelector)); } /** * Returns an Observable that emits a single Map, returned by a specified {@code mapFactory} function, that * contains an ArrayList of values, extracted by a specified {@code valueSelector} function from items * emitted by the source Observable and keyed by the {@code keySelector} function. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toMultiMap.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toMultiMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * the function that extracts a key from the source items to be used as the key in the Map * @param valueSelector * the function that extracts a value from the source items to be used as the value in the Map * @param mapFactory * the function that returns a Map instance to be used * @return an Observable that emits a single item: a Map that contains a list items mapped from the source * Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final <K, V> Observable<Map<K, Collection<V>>> toMultimap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector, Func0<? extends Map<K, Collection<V>>> mapFactory) { return lift(new OperatorToMultimap<T, K, V>(keySelector, valueSelector, mapFactory)); } /** * Returns an Observable that emits a single Map, returned by a specified {@code mapFactory} function, that * contains a custom collection of values, extracted by a specified {@code valueSelector} function from * items emitted by the source Observable, and keyed by the {@code keySelector} function. * <p> * <img width="640" height="305" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toMultiMap.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toMultiMap} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param keySelector * the function that extracts a key from the source items to be used as the key in the Map * @param valueSelector * the function that extracts a value from the source items to be used as the value in the Map * @param mapFactory * the function that returns a Map instance to be used * @param collectionFactory * the function that returns a Collection instance for a particular key to be used in the Map * @return an Observable that emits a single item: a Map that contains the collection of mapped items from * the source Observable * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final <K, V> Observable<Map<K, Collection<V>>> toMultimap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector, Func0<? extends Map<K, Collection<V>>> mapFactory, Func1<? super K, ? extends Collection<V>> collectionFactory) { return lift(new OperatorToMultimap<T, K, V>(keySelector, valueSelector, mapFactory, collectionFactory)); } /** * Returns an Observable that emits a list that contains the items emitted by the source Observable, in a * sorted order. Each item emitted by the Observable must implement {@link Comparable} with respect to all * other items in the sequence. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toSortedList.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toSortedList} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @throws ClassCastException * if any item emitted by the Observable does not implement {@link Comparable} with respect to * all other items emitted by the Observable * @return an Observable that emits a list that contains the items emitted by the source Observable in * sorted order * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final Observable<List<T>> toSortedList() { return lift(new OperatorToObservableSortedList<T>()); } /** * Returns an Observable that emits a list that contains the items emitted by the source Observable, in a * sorted order based on a specified comparison function. * <p> * <img width="640" height="310" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/toSortedList.f.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as by intent it is requesting and buffering everything.</dd> * <dt><b>Scheduler:</b></dt> * <dd>{@code toSortedList} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param sortFunction * a function that compares two items emitted by the source Observable and returns an Integer * that indicates their sort order * @return an Observable that emits a list that contains the items emitted by the source Observable in * sorted order * @see <a href="http://reactivex.io/documentation/operators/to.html">ReactiveX operators documentation: To</a> */ public final Observable<List<T>> toSortedList(Func2<? super T, ? super T, Integer> sortFunction) { return lift(new OperatorToObservableSortedList<T>(sortFunction)); } /** * Modifies the source Observable so that subscribers will unsubscribe from it on a specified * {@link Scheduler}. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param scheduler * the {@link Scheduler} to perform unsubscription actions on * @return the source Observable modified so that its unsubscriptions happen on the specified * {@link Scheduler} * @see <a href="http://reactivex.io/documentation/operators/subscribeon.html">ReactiveX operators documentation: SubscribeOn</a> */ public final Observable<T> unsubscribeOn(Scheduler scheduler) { return lift(new OperatorUnsubscribeOn<T>(scheduler)); } /** * Merges the specified Observable into this Observable sequence by using the {@code resultSelector} * function only when the source Observable (this instance) emits an item. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/withLatestFrom.png" alt=""> * * @warn "Backpressure Support" section missing from javadoc * @warn "Scheduler" section missing from javadoc * @param other * the other Observable * @param resultSelector * the function to call when this Observable emits an item and the other Observable has already * emitted an item, to generate the item to be emitted by the resulting Observable * @return an Observable that merges the specified Observable into this Observable by using the * {@code resultSelector} function only when the source Observable sequence (this instance) emits an * item * @Experimental The behavior of this can change at any time. * @since (if this graduates from Experimental/Beta to supported, replace this parenthetical with the release number) * @see <a href="http://reactivex.io/documentation/operators/combinelatest.html">ReactiveX operators documentation: CombineLatest</a> */ @Experimental public final <U, R> Observable<R> withLatestFrom(Observable<? extends U> other, Func2<? super T, ? super U, ? extends R> resultSelector) { return lift(new OperatorWithLatestFrom<T, U, R>(other, resultSelector)); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping windows. It emits the current window and opens a new one * whenever the Observable produced by the specified {@code closingSelector} emits an item. * <p> * <img width="640" height="485" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window1.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses the {@code closingSelector} to control data * flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code window} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param closingSelector * a {@link Func0} that returns an {@code Observable} that governs the boundary between windows. * When this {@code Observable} emits an item, {@code window} emits the current window and begins * a new one. * @return an Observable that emits connected, non-overlapping windows of items from the source Observable * whenever {@code closingSelector} emits an item * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final <TClosing> Observable<Observable<T>> window(Func0<? extends Observable<? extends TClosing>> closingSelector) { return lift(new OperatorWindowWithObservable<T, TClosing>(closingSelector)); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping windows, each containing {@code count} items. When the source * Observable completes or encounters an error, the resulting Observable emits the current window and * propagates the notification from the source Observable. * <p> * <img width="640" height="400" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window3.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses {@code count} to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code window} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param count * the maximum size of each window before it should be emitted * @return an Observable that emits connected, non-overlapping windows, each containing at most * {@code count} items from the source Observable * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(int count) { return window(count, count); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable emits windows every {@code skip} items, each containing no more than {@code count} items. When * the source Observable completes or encounters an error, the resulting Observable emits the current window * and propagates the notification from the source Observable. * <p> * <img width="640" height="365" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window4.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses {@code count} to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code window} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param count * the maximum size of each window before it should be emitted * @param skip * how many items need to be skipped before starting a new window. Note that if {@code skip} and * {@code count} are equal this is the same operation as {@link #window(int)}. * @return an Observable that emits windows every {@code skip} items containing at most {@code count} items * from the source Observable * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(int count, int skip) { return lift(new OperatorWindowWithSize<T>(count, skip)); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable starts a new window periodically, as determined by the {@code timeshift} argument. It emits * each window after a fixed timespan, specified by the {@code timespan} argument. When the source * Observable completes or Observable completes or encounters an error, the resulting Observable emits the * current window and propagates the notification from the source Observable. * <p> * <img width="640" height="335" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window7.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code window} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timespan * the period of time each window collects items before it should be emitted * @param timeshift * the period of time after which a new window will be created * @param unit * the unit of time that applies to the {@code timespan} and {@code timeshift} arguments * @return an Observable that emits new windows periodically as a fixed timespan elapses * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(long timespan, long timeshift, TimeUnit unit) { return window(timespan, timeshift, unit, Integer.MAX_VALUE, Schedulers.computation()); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable starts a new window periodically, as determined by the {@code timeshift} argument. It emits * each window after a fixed timespan, specified by the {@code timespan} argument. When the source * Observable completes or Observable completes or encounters an error, the resulting Observable emits the * current window and propagates the notification from the source Observable. * <p> * <img width="640" height="335" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window7.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timespan * the period of time each window collects items before it should be emitted * @param timeshift * the period of time after which a new window will be created * @param unit * the unit of time that applies to the {@code timespan} and {@code timeshift} arguments * @param scheduler * the {@link Scheduler} to use when determining the end and start of a window * @return an Observable that emits new windows periodically as a fixed timespan elapses * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(long timespan, long timeshift, TimeUnit unit, Scheduler scheduler) { return window(timespan, timeshift, unit, Integer.MAX_VALUE, scheduler); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable starts a new window periodically, as determined by the {@code timeshift} argument or a maximum * size as specified by the {@code count} argument (whichever is reached first). It emits * each window after a fixed timespan, specified by the {@code timespan} argument. When the source * Observable completes or Observable completes or encounters an error, the resulting Observable emits the * current window and propagates the notification from the source Observable. * <p> * <img width="640" height="335" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window7.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timespan * the period of time each window collects items before it should be emitted * @param timeshift * the period of time after which a new window will be created * @param unit * the unit of time that applies to the {@code timespan} and {@code timeshift} arguments * @param count * the maximum size of each window before it should be emitted * @param scheduler * the {@link Scheduler} to use when determining the end and start of a window * @return an Observable that emits new windows periodically as a fixed timespan elapses * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(long timespan, long timeshift, TimeUnit unit, int count, Scheduler scheduler) { return lift(new OperatorWindowWithTime<T>(timespan, timeshift, unit, count, scheduler)); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping windows, each of a fixed duration specified by the * {@code timespan} argument. When the source Observable completes or encounters an error, the resulting * Observable emits the current window and propagates the notification from the source Observable. * <p> * <img width="640" height="375" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window5.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code window} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timespan * the period of time each window collects items before it should be emitted and replaced with a * new window * @param unit * the unit of time that applies to the {@code timespan} argument * @return an Observable that emits connected, non-overlapping windows represending items emitted by the * source Observable during fixed, consecutive durations * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(long timespan, TimeUnit unit) { return window(timespan, timespan, unit, Schedulers.computation()); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping windows, each of a fixed duration as specified by the * {@code timespan} argument or a maximum size as specified by the {@code count} argument (whichever is * reached first). When the source Observable completes or encounters an error, the resulting Observable * emits the current window and propagates the notification from the source Observable. * <p> * <img width="640" height="370" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window6.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code window} operates by default on the {@code computation} {@link Scheduler}.</dd> * </dl> * * @param timespan * the period of time each window collects items before it should be emitted and replaced with a * new window * @param unit * the unit of time that applies to the {@code timespan} argument * @param count * the maximum size of each window before it should be emitted * @return an Observable that emits connected, non-overlapping windows of items from the source Observable * that were emitted during a fixed duration of time or when the window has reached maximum capacity * (whichever occurs first) * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(long timespan, TimeUnit unit, int count) { return window(timespan, unit, count, Schedulers.computation()); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping windows, each of a fixed duration specified by the * {@code timespan} argument or a maximum size specified by the {@code count} argument (whichever is reached * first). When the source Observable completes or encounters an error, the resulting Observable emits the * current window and propagates the notification from the source Observable. * <p> * <img width="640" height="370" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window6.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timespan * the period of time each window collects items before it should be emitted and replaced with a * new window * @param unit * the unit of time which applies to the {@code timespan} argument * @param count * the maximum size of each window before it should be emitted * @param scheduler * the {@link Scheduler} to use when determining the end and start of a window * @return an Observable that emits connected, non-overlapping windows of items from the source Observable * that were emitted during a fixed duration of time or when the window has reached maximum capacity * (whichever occurs first) * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(long timespan, TimeUnit unit, int count, Scheduler scheduler) { return window(timespan, timespan, unit, count, scheduler); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable emits connected, non-overlapping windows, each of a fixed duration as specified by the * {@code timespan} argument. When the source Observable completes or encounters an error, the resulting * Observable emits the current window and propagates the notification from the source Observable. * <p> * <img width="640" height="375" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window5.s.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses time to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>you specify which {@link Scheduler} this operator will use</dd> * </dl> * * @param timespan * the period of time each window collects items before it should be emitted and replaced with a * new window * @param unit * the unit of time which applies to the {@code timespan} argument * @param scheduler * the {@link Scheduler} to use when determining the end and start of a window * @return an Observable that emits connected, non-overlapping windows containing items emitted by the * source Observable within a fixed duration * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final Observable<Observable<T>> window(long timespan, TimeUnit unit, Scheduler scheduler) { return window(timespan, unit, Integer.MAX_VALUE, scheduler); } /** * Returns an Observable that emits windows of items it collects from the source Observable. The resulting * Observable emits windows that contain those items emitted by the source Observable between the time when * the {@code windowOpenings} Observable emits an item and when the Observable returned by * {@code closingSelector} emits an item. * <p> * <img width="640" height="550" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window2.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses Observables to control data flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code window} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param windowOpenings * an Observable that, when it emits an item, causes another window to be created * @param closingSelector * a {@link Func1} that produces an Observable for every window created. When this Observable * emits an item, the associated window is closed and emitted * @return an Observable that emits windows of items emitted by the source Observable that are governed by * the specified window-governing Observables * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final <TOpening, TClosing> Observable<Observable<T>> window(Observable<? extends TOpening> windowOpenings, Func1<? super TOpening, ? extends Observable<? extends TClosing>> closingSelector) { return lift(new OperatorWindowWithStartEndObservable<T, TOpening, TClosing>(windowOpenings, closingSelector)); } /** * Returns an Observable that emits non-overlapping windows of items it collects from the source Observable * where the boundary of each window is determined by the items emitted from a specified boundary-governing * Observable. * <p> * <img width="640" height="475" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/window8.png" alt=""> * <dl> * <dt><b>Backpressure Support:</b></dt> * <dd>This operator does not support backpressure as it uses a {@code boundary} Observable to control data * flow.</dd> * <dt><b>Scheduler:</b></dt> * <dd>This version of {@code window} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <U> * the window element type (ignored) * @param boundary * an Observable whose emitted items close and open windows * @return an Observable that emits non-overlapping windows of items it collects from the source Observable * where the boundary of each window is determined by the items emitted from the {@code boundary} * Observable * @see <a href="http://reactivex.io/documentation/operators/window.html">ReactiveX operators documentation: Window</a> */ public final <U> Observable<Observable<T>> window(Observable<U> boundary) { return lift(new OperatorWindowWithObservable<T, U>(boundary)); } /** * Returns an Observable that emits items that are the result of applying a specified function to pairs of * values, one each from the source Observable and a specified Iterable sequence. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.i.png" alt=""> * <p> * Note that the {@code other} Iterable is evaluated as items are observed from the source Observable; it is * not pre-consumed. This allows you to zip infinite streams on either side. * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zipWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <T2> * the type of items in the {@code other} Iterable * @param <R> * the type of items emitted by the resulting Observable * @param other * the Iterable sequence * @param zipFunction * a function that combines the pairs of items from the Observable and the Iterable to generate * the items to be emitted by the resulting Observable * @return an Observable that pairs up values from the source Observable and the {@code other} Iterable * sequence and emits the results of {@code zipFunction} applied to these pairs * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final <T2, R> Observable<R> zipWith(Iterable<? extends T2> other, Func2<? super T, ? super T2, ? extends R> zipFunction) { return lift(new OperatorZipIterable<T, T2, R>(other, zipFunction)); } /** * Returns an Observable that emits items that are the result of applying a specified function to pairs of * values, one each from the source Observable and another specified Observable. * <p> * <img width="640" height="380" src="https://raw.github.com/wiki/ReactiveX/RxJava/images/rx-operators/zip.png" alt=""> * <dl> * <dt><b>Scheduler:</b></dt> * <dd>{@code zipWith} does not operate by default on a particular {@link Scheduler}.</dd> * </dl> * * @param <T2> * the type of items emitted by the {@code other} Observable * @param <R> * the type of items emitted by the resulting Observable * @param other * the other Observable * @param zipFunction * a function that combines the pairs of items from the two Observables to generate the items to * be emitted by the resulting Observable * @return an Observable that pairs up values from the source Observable and the {@code other} Observable * and emits the results of {@code zipFunction} applied to these pairs * @see <a href="http://reactivex.io/documentation/operators/zip.html">ReactiveX operators documentation: Zip</a> */ public final <T2, R> Observable<R> zipWith(Observable<? extends T2> other, Func2<? super T, ? super T2, ? extends R> zipFunction) { return zip(this, other, zipFunction); } /** * An Observable that never sends any information to an {@link Observer}. * This Observable is useful primarily for testing purposes. * * @param <T> * the type of item (not) emitted by the Observable */ private static class NeverObservable<T> extends Observable<T> { public NeverObservable() { super(new OnSubscribe<T>() { @Override public void call(Subscriber<? super T> observer) { // do nothing } }); } } /** * An Observable that invokes {@link Observer#onError onError} when the {@link Observer} subscribes to it. * * @param <T> * the type of item (ostensibly) emitted by the Observable */ private static class ThrowObservable<T> extends Observable<T> { public ThrowObservable(final Throwable exception) { super(new OnSubscribe<T>() { /** * Accepts an {@link Observer} and calls its {@link Observer#onError onError} method. * * @param observer * an {@link Observer} of this Observable */ @Override public void call(Subscriber<? super T> observer) { observer.onError(exception); } }); } } }