/**
* 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.flowable;
import java.util.concurrent.Callable;
import java.util.concurrent.atomic.*;
import org.reactivestreams.*;
import io.reactivex.Flowable;
import io.reactivex.disposables.Disposable;
import io.reactivex.exceptions.*;
import io.reactivex.internal.disposables.DisposableHelper;
import io.reactivex.internal.functions.ObjectHelper;
import io.reactivex.internal.fuseable.SimplePlainQueue;
import io.reactivex.internal.queue.MpscLinkedQueue;
import io.reactivex.internal.subscribers.QueueDrainSubscriber;
import io.reactivex.internal.subscriptions.SubscriptionHelper;
import io.reactivex.internal.util.NotificationLite;
import io.reactivex.plugins.RxJavaPlugins;
import io.reactivex.processors.UnicastProcessor;
import io.reactivex.subscribers.*;
public final class FlowableWindowBoundarySupplier<T, B> extends AbstractFlowableWithUpstream<T, Flowable<T>> {
final Callable<? extends Publisher<B>> other;
final int bufferSize;
public FlowableWindowBoundarySupplier(Flowable<T> source,
Callable<? extends Publisher<B>> other, int bufferSize) {
super(source);
this.other = other;
this.bufferSize = bufferSize;
}
@Override
protected void subscribeActual(Subscriber<? super Flowable<T>> s) {
source.subscribe(new WindowBoundaryMainSubscriber<T, B>(
new SerializedSubscriber<Flowable<T>>(s), other, bufferSize));
}
static final class WindowBoundaryMainSubscriber<T, B>
extends QueueDrainSubscriber<T, Object, Flowable<T>>
implements Subscription {
final Callable<? extends Publisher<B>> other;
final int bufferSize;
Subscription s;
final AtomicReference<Disposable> boundary = new AtomicReference<Disposable>();
UnicastProcessor<T> window;
static final Object NEXT = new Object();
final AtomicLong windows = new AtomicLong();
WindowBoundaryMainSubscriber(Subscriber<? super Flowable<T>> actual, Callable<? extends Publisher<B>> other,
int bufferSize) {
super(actual, new MpscLinkedQueue<Object>());
this.other = other;
this.bufferSize = bufferSize;
windows.lazySet(1);
}
@Override
public void onSubscribe(Subscription s) {
if (SubscriptionHelper.validate(this.s, s)) {
this.s = s;
Subscriber<? super Flowable<T>> a = actual;
a.onSubscribe(this);
if (cancelled) {
return;
}
Publisher<B> p;
try {
p = ObjectHelper.requireNonNull(other.call(), "The first window publisher supplied is null");
} catch (Throwable e) {
Exceptions.throwIfFatal(e);
s.cancel();
a.onError(e);
return;
}
UnicastProcessor<T> w = UnicastProcessor.<T>create(bufferSize);
long r = requested();
if (r != 0L) {
a.onNext(w);
if (r != Long.MAX_VALUE) {
produced(1);
}
} else {
s.cancel();
a.onError(new MissingBackpressureException("Could not deliver first window due to lack of requests"));
return;
}
window = w;
WindowBoundaryInnerSubscriber<T, B> inner = new WindowBoundaryInnerSubscriber<T, B>(this);
if (boundary.compareAndSet(null, inner)) {
windows.getAndIncrement();
s.request(Long.MAX_VALUE);
p.subscribe(inner);
}
}
}
@Override
public void onNext(T t) {
if (done) {
return;
}
if (fastEnter()) {
UnicastProcessor<T> w = window;
w.onNext(t);
if (leave(-1) == 0) {
return;
}
} else {
queue.offer(NotificationLite.next(t));
if (!enter()) {
return;
}
}
drainLoop();
}
@Override
public void onError(Throwable t) {
if (done) {
RxJavaPlugins.onError(t);
return;
}
error = t;
done = true;
if (enter()) {
drainLoop();
}
if (windows.decrementAndGet() == 0) {
DisposableHelper.dispose(boundary);
}
actual.onError(t);
}
@Override
public void onComplete() {
if (done) {
return;
}
done = true;
if (enter()) {
drainLoop();
}
if (windows.decrementAndGet() == 0) {
DisposableHelper.dispose(boundary);
}
actual.onComplete();
}
@Override
public void request(long n) {
requested(n);
}
@Override
public void cancel() {
cancelled = true;
}
void drainLoop() {
final SimplePlainQueue<Object> q = queue;
final Subscriber<? super Flowable<T>> a = actual;
int missed = 1;
UnicastProcessor<T> w = window;
for (;;) {
for (;;) {
boolean d = done;
Object o = q.poll();
boolean empty = o == null;
if (d && empty) {
DisposableHelper.dispose(boundary);
Throwable e = error;
if (e != null) {
w.onError(e);
} else {
w.onComplete();
}
return;
}
if (empty) {
break;
}
if (o == NEXT) {
w.onComplete();
if (windows.decrementAndGet() == 0) {
DisposableHelper.dispose(boundary);
return;
}
if (cancelled) {
continue;
}
Publisher<B> p;
try {
p = ObjectHelper.requireNonNull(other.call(), "The publisher supplied is null");
} catch (Throwable e) {
Exceptions.throwIfFatal(e);
DisposableHelper.dispose(boundary);
a.onError(e);
return;
}
w = UnicastProcessor.<T>create(bufferSize);
long r = requested();
if (r != 0L) {
windows.getAndIncrement();
a.onNext(w);
if (r != Long.MAX_VALUE) {
produced(1);
}
} else {
// don't emit new windows
cancelled = true;
a.onError(new MissingBackpressureException("Could not deliver new window due to lack of requests"));
continue;
}
window = w;
WindowBoundaryInnerSubscriber<T, B> b = new WindowBoundaryInnerSubscriber<T, B>(this);
if (boundary.compareAndSet(boundary.get(), b)) {
p.subscribe(b);
}
continue;
}
w.onNext(NotificationLite.<T>getValue(o));
}
missed = leave(-missed);
if (missed == 0) {
return;
}
}
}
void next() {
queue.offer(NEXT);
if (enter()) {
drainLoop();
}
}
}
static final class WindowBoundaryInnerSubscriber<T, B> extends DisposableSubscriber<B> {
final WindowBoundaryMainSubscriber<T, B> parent;
boolean done;
WindowBoundaryInnerSubscriber(WindowBoundaryMainSubscriber<T, B> parent) {
this.parent = parent;
}
@Override
public void onNext(B t) {
if (done) {
return;
}
done = true;
cancel();
parent.next();
}
@Override
public void onError(Throwable t) {
if (done) {
RxJavaPlugins.onError(t);
return;
}
done = true;
parent.onError(t);
}
@Override
public void onComplete() {
if (done) {
return;
}
done = true;
parent.onComplete();
// parent.next();
}
}
}