/** * 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.functions; import rx.Observer; /** * Utility class for the Action interfaces. */ public final class Actions { private Actions() { throw new IllegalStateException("No instances!"); } @SuppressWarnings("unchecked") public static final <T0, T1, T2, T3, T4, T5, T6, T7, T8, T9> EmptyAction<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9> empty() { return (EmptyAction<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9>) EMPTY_ACTION; } @SuppressWarnings("rawtypes") private static final EmptyAction EMPTY_ACTION = new EmptyAction(); private static final class EmptyAction<T0, T1, T2, T3, T4, T5, T6, T7, T8, T9> implements Action0, Action1<T0>, Action2<T0, T1>, Action3<T0, T1, T2>, Action4<T0, T1, T2, T3>, Action5<T0, T1, T2, T3, T4>, Action6<T0, T1, T2, T3, T4, T5>, Action7<T0, T1, T2, T3, T4, T5, T6>, Action8<T0, T1, T2, T3, T4, T5, T6, T7>, Action9<T0, T1, T2, T3, T4, T5, T6, T7, T8>, ActionN { @Override public void call() { } @Override public void call(T0 t1) { } @Override public void call(T0 t1, T1 t2) { } @Override public void call(T0 t1, T1 t2, T2 t3) { } @Override public void call(T0 t1, T1 t2, T2 t3, T3 t4) { } @Override public void call(T0 t1, T1 t2, T2 t3, T3 t4, T4 t5) { } @Override public void call(T0 t1, T1 t2, T2 t3, T3 t4, T4 t5, T5 t6) { } @Override public void call(T0 t1, T1 t2, T2 t3, T3 t4, T4 t5, T5 t6, T6 t7) { } @Override public void call(T0 t1, T1 t2, T2 t3, T3 t4, T4 t5, T5 t6, T6 t7, T7 t8) { } @Override public void call(T0 t1, T1 t2, T2 t3, T3 t4, T4 t5, T5 t6, T6 t7, T7 t8, T8 t9) { } @Override public void call(Object... args) { } } /** * Extracts a method reference to the Observer's {@link Observer#onNext onNext} method in the form of an * {@link Action1}. * <p>Java 8: observer::onNext</p> * * @param observer * the {@link Observer} to use * @return an action which calls observer's {@code onNext} method. */ public static <T> Action1<T> onNextFrom(final Observer<T> observer) { return new Action1<T>() { @Override public void call(T t1) { observer.onNext(t1); } }; } /** * Extracts a method reference to the Observer's {@link Observer#onError(java.lang.Throwable) onError} * method in the form of an {@link Action1}. * <p>Java 8: observer::onError</p> * * @param observer * the {@link Observer} to use * @return an action which calls observer's {@code onError} method. */ public static <T> Action1<Throwable> onErrorFrom(final Observer<T> observer) { return new Action1<Throwable>() { @Override public void call(Throwable t1) { observer.onError(t1); } }; } /** * Extracts a method reference to the Observer's {@link Observer#onCompleted() onCompleted} method in the * form of an {@link Action0}. * <p>Java 8: observer::onCompleted</p> * * @param observer * the {@link Observer} to use * @return an action which calls observer's {@code onCompleted} method. */ public static <T> Action0 onCompletedFrom(final Observer<T> observer) { return new Action0() { @Override public void call() { observer.onCompleted(); } }; } /** * Converts an {@link Action0} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action0} to convert * @return a {@link Func0} that calls {@code action} and returns {@code null} */ public static Func0<Void> toFunc(final Action0 action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action1} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action1} to convert * @return a {@link Func1} that calls {@code action} and returns {@code null} */ public static <T1> Func1<T1, Void> toFunc(final Action1<T1> action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action2} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action2} to convert * @return a {@link Func2} that calls {@code action} and returns {@code null} */ public static <T1, T2> Func2<T1, T2, Void> toFunc(final Action2<T1, T2> action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action3} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action3} to convert * @return a {@link Func3} that calls {@code action} and returns {@code null} */ public static <T1, T2, T3> Func3<T1, T2, T3, Void> toFunc(final Action3<T1, T2, T3> action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action4} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action4} to convert * @return a {@link Func4} that calls {@code action} and returns {@code null} */ public static <T1, T2, T3, T4> Func4<T1, T2, T3, T4, Void> toFunc(final Action4<T1, T2, T3, T4> action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action5} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action5} to convert * @return a {@link Func5} that calls {@code action} and returns {@code null} */ public static <T1, T2, T3, T4, T5> Func5<T1, T2, T3, T4, T5, Void> toFunc( final Action5<T1, T2, T3, T4, T5> action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action6} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action6} to convert * @return a {@link Func6} that calls {@code action} and returns {@code null} */ public static <T1, T2, T3, T4, T5, T6> Func6<T1, T2, T3, T4, T5, T6, Void> toFunc( final Action6<T1, T2, T3, T4, T5, T6> action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action7} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action7} to convert * @return a {@link Func7} that calls {@code action} and returns {@code null} */ public static <T1, T2, T3, T4, T5, T6, T7> Func7<T1, T2, T3, T4, T5, T6, T7, Void> toFunc( final Action7<T1, T2, T3, T4, T5, T6, T7> action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action8} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action8} to convert * @return a {@link Func8} that calls {@code action} and returns {@code null} */ public static <T1, T2, T3, T4, T5, T6, T7, T8> Func8<T1, T2, T3, T4, T5, T6, T7, T8, Void> toFunc( final Action8<T1, T2, T3, T4, T5, T6, T7, T8> action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action9} to a function that calls the action and returns {@code null}. * * @param action * the {@link Action9} to convert * @return a {@link Func9} that calls {@code action} and returns {@code null} */ public static <T1, T2, T3, T4, T5, T6, T7, T8, T9> Func9<T1, T2, T3, T4, T5, T6, T7, T8, T9, Void> toFunc( final Action9<T1, T2, T3, T4, T5, T6, T7, T8, T9> action) { return toFunc(action, (Void) null); } /** * Converts an {@link ActionN} to a function that calls the action and returns {@code null}. * * @param action * the {@link ActionN} to convert * @return a {@link FuncN} that calls {@code action} and returns {@code null} */ public static FuncN<Void> toFunc( final ActionN action) { return toFunc(action, (Void) null); } /** * Converts an {@link Action0} to a function that calls the action and returns a specified value. * * @param action * the {@link Action0} to convert * @param result * the value to return from the function call * @return a {@link Func0} that calls {@code action} and returns {@code result} */ public static <R> Func0<R> toFunc(final Action0 action, final R result) { return new Func0<R>() { @Override public R call() { action.call(); return result; } }; } /** * Converts an {@link Action1} to a function that calls the action and returns a specified value. * * @param action * the {@link Action1} to convert * @param result * the value to return from the function call * @return a {@link Func1} that calls {@code action} and returns {@code result} */ public static <T1, R> Func1<T1, R> toFunc(final Action1<T1> action, final R result) { return new Func1<T1, R>() { @Override public R call(T1 t1) { action.call(t1); return result; } }; } /** * Converts an {@link Action2} to a function that calls the action and returns a specified value. * * @param action * the {@link Action2} to convert * @param result * the value to return from the function call * @return a {@link Func2} that calls {@code action} and returns {@code result} */ public static <T1, T2, R> Func2<T1, T2, R> toFunc(final Action2<T1, T2> action, final R result) { return new Func2<T1, T2, R>() { @Override public R call(T1 t1, T2 t2) { action.call(t1, t2); return result; } }; } /** * Converts an {@link Action3} to a function that calls the action and returns a specified value. * * @param action * the {@link Action3} to convert * @param result * the value to return from the function call * @return a {@link Func3} that calls {@code action} and returns {@code result} */ public static <T1, T2, T3, R> Func3<T1, T2, T3, R> toFunc(final Action3<T1, T2, T3> action, final R result) { return new Func3<T1, T2, T3, R>() { @Override public R call(T1 t1, T2 t2, T3 t3) { action.call(t1, t2, t3); return result; } }; } /** * Converts an {@link Action4} to a function that calls the action and returns a specified value. * * @param action * the {@link Action4} to convert * @param result * the value to return from the function call * @return a {@link Func4} that calls {@code action} and returns {@code result} */ public static <T1, T2, T3, T4, R> Func4<T1, T2, T3, T4, R> toFunc(final Action4<T1, T2, T3, T4> action, final R result) { return new Func4<T1, T2, T3, T4, R>() { @Override public R call(T1 t1, T2 t2, T3 t3, T4 t4) { action.call(t1, t2, t3, t4); return result; } }; } /** * Converts an {@link Action5} to a function that calls the action and returns a specified value. * * @param action * the {@link Action5} to convert * @param result * the value to return from the function call * @return a {@link Func5} that calls {@code action} and returns {@code result} */ public static <T1, T2, T3, T4, T5, R> Func5<T1, T2, T3, T4, T5, R> toFunc( final Action5<T1, T2, T3, T4, T5> action, final R result) { return new Func5<T1, T2, T3, T4, T5, R>() { @Override public R call(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5) { action.call(t1, t2, t3, t4, t5); return result; } }; } /** * Converts an {@link Action6} to a function that calls the action and returns a specified value. * * @param action * the {@link Action6} to convert * @param result * the value to return from the function call * @return a {@link Func6} that calls {@code action} and returns {@code result} */ public static <T1, T2, T3, T4, T5, T6, R> Func6<T1, T2, T3, T4, T5, T6, R> toFunc( final Action6<T1, T2, T3, T4, T5, T6> action, final R result) { return new Func6<T1, T2, T3, T4, T5, T6, R>() { @Override public R call(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6) { action.call(t1, t2, t3, t4, t5, t6); return result; } }; } /** * Converts an {@link Action7} to a function that calls the action and returns a specified value. * * @param action * the {@link Action7} to convert * @param result * the value to return from the function call * @return a {@link Func7} that calls {@code action} and returns {@code result} */ public static <T1, T2, T3, T4, T5, T6, T7, R> Func7<T1, T2, T3, T4, T5, T6, T7, R> toFunc( final Action7<T1, T2, T3, T4, T5, T6, T7> action, final R result) { return new Func7<T1, T2, T3, T4, T5, T6, T7, R>() { @Override public R call(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6, T7 t7) { action.call(t1, t2, t3, t4, t5, t6, t7); return result; } }; } /** * Converts an {@link Action8} to a function that calls the action and returns a specified value. * * @param action * the {@link Action8} to convert * @param result * the value to return from the function call * @return a {@link Func8} that calls {@code action} and returns {@code result} */ public static <T1, T2, T3, T4, T5, T6, T7, T8, R> Func8<T1, T2, T3, T4, T5, T6, T7, T8, R> toFunc( final Action8<T1, T2, T3, T4, T5, T6, T7, T8> action, final R result) { return new Func8<T1, T2, T3, T4, T5, T6, T7, T8, R>() { @Override public R call(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6, T7 t7, T8 t8) { action.call(t1, t2, t3, t4, t5, t6, t7, t8); return result; } }; } /** * Converts an {@link Action9} to a function that calls the action and returns a specified value. * * @param action * the {@link Action9} to convert * @param result * the value to return from the function call * @return a {@link Func9} that calls {@code action} and returns {@code result} */ public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, R> Func9<T1, T2, T3, T4, T5, T6, T7, T8, T9, R> toFunc( final Action9<T1, T2, T3, T4, T5, T6, T7, T8, T9> action, final R result) { return new Func9<T1, T2, T3, T4, T5, T6, T7, T8, T9, R>() { @Override public R call(T1 t1, T2 t2, T3 t3, T4 t4, T5 t5, T6 t6, T7 t7, T8 t8, T9 t9) { action.call(t1, t2, t3, t4, t5, t6, t7, t8, t9); return result; } }; } /** * Converts an {@link ActionN} to a function that calls the action and returns a specified value. * * @param action * the {@link ActionN} to convert * @param result * the value to return from the function call * @return a {@link FuncN} that calls {@code action} and returns {@code result} */ public static <R> FuncN<R> toFunc( final ActionN action, final R result) { return new FuncN<R>() { @Override public R call(Object... args) { action.call(args); return result; } }; } }