/**
* Copyright (c) 2016-present, RxJava Contributors.
*
* 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 io.reactivex.internal.operators.observable;
import java.util.concurrent.Callable;
import java.util.concurrent.atomic.AtomicInteger;
import io.reactivex.*;
import io.reactivex.disposables.Disposable;
import io.reactivex.exceptions.Exceptions;
import io.reactivex.functions.Function;
import io.reactivex.internal.disposables.*;
import io.reactivex.internal.functions.ObjectHelper;
import io.reactivex.internal.fuseable.*;
import io.reactivex.internal.queue.SpscLinkedArrayQueue;
import io.reactivex.internal.util.*;
import io.reactivex.observers.SerializedObserver;
import io.reactivex.plugins.RxJavaPlugins;
public final class ObservableConcatMap<T, U> extends AbstractObservableWithUpstream<T, U> {
final Function<? super T, ? extends ObservableSource<? extends U>> mapper;
final int bufferSize;
final ErrorMode delayErrors;
public ObservableConcatMap(ObservableSource<T> source, Function<? super T, ? extends ObservableSource<? extends U>> mapper,
int bufferSize, ErrorMode delayErrors) {
super(source);
this.mapper = mapper;
this.delayErrors = delayErrors;
this.bufferSize = Math.max(8, bufferSize);
}
@Override
public void subscribeActual(Observer<? super U> s) {
if (ObservableScalarXMap.tryScalarXMapSubscribe(source, s, mapper)) {
return;
}
if (delayErrors == ErrorMode.IMMEDIATE) {
SerializedObserver<U> serial = new SerializedObserver<U>(s);
source.subscribe(new SourceObserver<T, U>(serial, mapper, bufferSize));
} else {
source.subscribe(new ConcatMapDelayErrorObserver<T, U>(s, mapper, bufferSize, delayErrors == ErrorMode.END));
}
}
static final class SourceObserver<T, U> extends AtomicInteger implements Observer<T>, Disposable {
private static final long serialVersionUID = 8828587559905699186L;
final Observer<? super U> actual;
final SequentialDisposable sa;
final Function<? super T, ? extends ObservableSource<? extends U>> mapper;
final Observer<U> inner;
final int bufferSize;
SimpleQueue<T> queue;
Disposable s;
volatile boolean active;
volatile boolean disposed;
volatile boolean done;
int fusionMode;
SourceObserver(Observer<? super U> actual,
Function<? super T, ? extends ObservableSource<? extends U>> mapper, int bufferSize) {
this.actual = actual;
this.mapper = mapper;
this.bufferSize = bufferSize;
this.inner = new InnerObserver<U>(actual, this);
this.sa = new SequentialDisposable();
}
@Override
public void onSubscribe(Disposable s) {
if (DisposableHelper.validate(this.s, s)) {
this.s = s;
if (s instanceof QueueDisposable) {
@SuppressWarnings("unchecked")
QueueDisposable<T> qd = (QueueDisposable<T>) s;
int m = qd.requestFusion(QueueDisposable.ANY);
if (m == QueueDisposable.SYNC) {
fusionMode = m;
queue = qd;
done = true;
actual.onSubscribe(this);
drain();
return;
}
if (m == QueueDisposable.ASYNC) {
fusionMode = m;
queue = qd;
actual.onSubscribe(this);
return;
}
}
queue = new SpscLinkedArrayQueue<T>(bufferSize);
actual.onSubscribe(this);
}
}
@Override
public void onNext(T t) {
if (done) {
return;
}
if (fusionMode == QueueDisposable.NONE) {
queue.offer(t);
}
drain();
}
@Override
public void onError(Throwable t) {
if (done) {
RxJavaPlugins.onError(t);
return;
}
done = true;
dispose();
actual.onError(t);
}
@Override
public void onComplete() {
if (done) {
return;
}
done = true;
drain();
}
void innerComplete() {
active = false;
drain();
}
@Override
public boolean isDisposed() {
return disposed;
}
@Override
public void dispose() {
disposed = true;
sa.dispose();
s.dispose();
if (getAndIncrement() == 0) {
queue.clear();
}
}
void innerSubscribe(Disposable s) {
sa.update(s);
}
void drain() {
if (getAndIncrement() != 0) {
return;
}
for (;;) {
if (disposed) {
queue.clear();
return;
}
if (!active) {
boolean d = done;
T t;
try {
t = queue.poll();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
dispose();
queue.clear();
actual.onError(ex);
return;
}
boolean empty = t == null;
if (d && empty) {
actual.onComplete();
return;
}
if (!empty) {
ObservableSource<? extends U> o;
try {
o = ObjectHelper.requireNonNull(mapper.apply(t), "The mapper returned a null ObservableSource");
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
dispose();
queue.clear();
actual.onError(ex);
return;
}
active = true;
o.subscribe(inner);
}
}
if (decrementAndGet() == 0) {
break;
}
}
}
static final class InnerObserver<U> implements Observer<U> {
final Observer<? super U> actual;
final SourceObserver<?, ?> parent;
InnerObserver(Observer<? super U> actual, SourceObserver<?, ?> parent) {
this.actual = actual;
this.parent = parent;
}
@Override
public void onSubscribe(Disposable s) {
parent.innerSubscribe(s);
}
@Override
public void onNext(U t) {
actual.onNext(t);
}
@Override
public void onError(Throwable t) {
parent.dispose();
actual.onError(t);
}
@Override
public void onComplete() {
parent.innerComplete();
}
}
}
static final class ConcatMapDelayErrorObserver<T, R>
extends AtomicInteger
implements Observer<T>, Disposable {
private static final long serialVersionUID = -6951100001833242599L;
final Observer<? super R> actual;
final Function<? super T, ? extends ObservableSource<? extends R>> mapper;
final int bufferSize;
final AtomicThrowable error;
final DelayErrorInnerObserver<R> observer;
final SequentialDisposable arbiter;
final boolean tillTheEnd;
SimpleQueue<T> queue;
Disposable d;
volatile boolean active;
volatile boolean done;
volatile boolean cancelled;
int sourceMode;
ConcatMapDelayErrorObserver(Observer<? super R> actual,
Function<? super T, ? extends ObservableSource<? extends R>> mapper, int bufferSize,
boolean tillTheEnd) {
this.actual = actual;
this.mapper = mapper;
this.bufferSize = bufferSize;
this.tillTheEnd = tillTheEnd;
this.error = new AtomicThrowable();
this.observer = new DelayErrorInnerObserver<R>(actual, this);
this.arbiter = new SequentialDisposable();
}
@Override
public void onSubscribe(Disposable d) {
if (DisposableHelper.validate(this.d, d)) {
this.d = d;
if (d instanceof QueueDisposable) {
@SuppressWarnings("unchecked")
QueueDisposable<T> qd = (QueueDisposable<T>) d;
int m = qd.requestFusion(QueueDisposable.ANY);
if (m == QueueDisposable.SYNC) {
sourceMode = m;
queue = qd;
done = true;
actual.onSubscribe(this);
drain();
return;
}
if (m == QueueDisposable.ASYNC) {
sourceMode = m;
queue = qd;
actual.onSubscribe(this);
return;
}
}
queue = new SpscLinkedArrayQueue<T>(bufferSize);
actual.onSubscribe(this);
}
}
@Override
public void onNext(T value) {
if (sourceMode == QueueDisposable.NONE) {
queue.offer(value);
}
drain();
}
@Override
public void onError(Throwable e) {
if (error.addThrowable(e)) {
done = true;
drain();
} else {
RxJavaPlugins.onError(e);
}
}
@Override
public void onComplete() {
done = true;
drain();
}
@Override
public boolean isDisposed() {
return d.isDisposed();
}
@Override
public void dispose() {
cancelled = true;
d.dispose();
arbiter.dispose();
}
@SuppressWarnings("unchecked")
void drain() {
if (getAndIncrement() != 0) {
return;
}
Observer<? super R> actual = this.actual;
SimpleQueue<T> queue = this.queue;
AtomicThrowable error = this.error;
for (;;) {
if (!active) {
if (cancelled) {
queue.clear();
return;
}
if (!tillTheEnd) {
Throwable ex = error.get();
if (ex != null) {
queue.clear();
actual.onError(error.terminate());
return;
}
}
boolean d = done;
T v;
try {
v = queue.poll();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
this.d.dispose();
error.addThrowable(ex);
actual.onError(error.terminate());
return;
}
boolean empty = v == null;
if (d && empty) {
Throwable ex = error.terminate();
if (ex != null) {
actual.onError(ex);
} else {
actual.onComplete();
}
return;
}
if (!empty) {
ObservableSource<? extends R> o;
try {
o = ObjectHelper.requireNonNull(mapper.apply(v), "The mapper returned a null ObservableSource");
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
this.d.dispose();
queue.clear();
error.addThrowable(ex);
actual.onError(error.terminate());
return;
}
if (o instanceof Callable) {
R w;
try {
w = ((Callable<R>)o).call();
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
error.addThrowable(ex);
continue;
}
if (w != null && !cancelled) {
actual.onNext(w);
}
continue;
} else {
active = true;
o.subscribe(observer);
}
}
}
if (decrementAndGet() == 0) {
break;
}
}
}
static final class DelayErrorInnerObserver<R> implements Observer<R> {
final Observer<? super R> actual;
final ConcatMapDelayErrorObserver<?, R> parent;
DelayErrorInnerObserver(Observer<? super R> actual, ConcatMapDelayErrorObserver<?, R> parent) {
this.actual = actual;
this.parent = parent;
}
@Override
public void onSubscribe(Disposable d) {
parent.arbiter.replace(d);
}
@Override
public void onNext(R value) {
actual.onNext(value);
}
@Override
public void onError(Throwable e) {
ConcatMapDelayErrorObserver<?, R> p = parent;
if (p.error.addThrowable(e)) {
if (!p.tillTheEnd) {
p.d.dispose();
}
p.active = false;
p.drain();
} else {
RxJavaPlugins.onError(e);
}
}
@Override
public void onComplete() {
ConcatMapDelayErrorObserver<?, R> p = parent;
p.active = false;
p.drain();
}
}
}
}