/** * 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 io.reactivex.*; import io.reactivex.annotations.Nullable; import io.reactivex.disposables.Disposable; import io.reactivex.exceptions.Exceptions; import io.reactivex.internal.disposables.DisposableHelper; import io.reactivex.internal.fuseable.*; import io.reactivex.internal.observers.BasicIntQueueDisposable; import io.reactivex.internal.queue.SpscLinkedArrayQueue; import io.reactivex.internal.schedulers.TrampolineScheduler; import io.reactivex.plugins.RxJavaPlugins; public final class ObservableObserveOn<T> extends AbstractObservableWithUpstream<T, T> { final Scheduler scheduler; final boolean delayError; final int bufferSize; public ObservableObserveOn(ObservableSource<T> source, Scheduler scheduler, boolean delayError, int bufferSize) { super(source); this.scheduler = scheduler; this.delayError = delayError; this.bufferSize = bufferSize; } @Override protected void subscribeActual(Observer<? super T> observer) { if (scheduler instanceof TrampolineScheduler) { source.subscribe(observer); } else { Scheduler.Worker w = scheduler.createWorker(); source.subscribe(new ObserveOnObserver<T>(observer, w, delayError, bufferSize)); } } static final class ObserveOnObserver<T> extends BasicIntQueueDisposable<T> implements Observer<T>, Runnable { private static final long serialVersionUID = 6576896619930983584L; final Observer<? super T> actual; final Scheduler.Worker worker; final boolean delayError; final int bufferSize; SimpleQueue<T> queue; Disposable s; Throwable error; volatile boolean done; volatile boolean cancelled; int sourceMode; boolean outputFused; ObserveOnObserver(Observer<? super T> actual, Scheduler.Worker worker, boolean delayError, int bufferSize) { this.actual = actual; this.worker = worker; this.delayError = delayError; this.bufferSize = bufferSize; } @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 | QueueDisposable.BOUNDARY); if (m == QueueDisposable.SYNC) { sourceMode = m; queue = qd; done = true; actual.onSubscribe(this); schedule(); 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 t) { if (done) { return; } if (sourceMode != QueueDisposable.ASYNC) { queue.offer(t); } schedule(); } @Override public void onError(Throwable t) { if (done) { RxJavaPlugins.onError(t); return; } error = t; done = true; schedule(); } @Override public void onComplete() { if (done) { return; } done = true; schedule(); } @Override public void dispose() { if (!cancelled) { cancelled = true; s.dispose(); worker.dispose(); if (getAndIncrement() == 0) { queue.clear(); } } } @Override public boolean isDisposed() { return cancelled; } void schedule() { if (getAndIncrement() == 0) { worker.schedule(this); } } void drainNormal() { int missed = 1; final SimpleQueue<T> q = queue; final Observer<? super T> a = actual; for (;;) { if (checkTerminated(done, q.isEmpty(), a)) { return; } for (;;) { boolean d = done; T v; try { v = q.poll(); } catch (Throwable ex) { Exceptions.throwIfFatal(ex); s.dispose(); q.clear(); a.onError(ex); worker.dispose(); return; } boolean empty = v == null; if (checkTerminated(d, empty, a)) { return; } if (empty) { break; } a.onNext(v); } missed = addAndGet(-missed); if (missed == 0) { break; } } } void drainFused() { int missed = 1; for (;;) { if (cancelled) { return; } boolean d = done; Throwable ex = error; if (!delayError && d && ex != null) { actual.onError(error); worker.dispose(); return; } actual.onNext(null); if (d) { ex = error; if (ex != null) { actual.onError(ex); } else { actual.onComplete(); } worker.dispose(); return; } missed = addAndGet(-missed); if (missed == 0) { break; } } } @Override public void run() { if (outputFused) { drainFused(); } else { drainNormal(); } } boolean checkTerminated(boolean d, boolean empty, Observer<? super T> a) { if (cancelled) { queue.clear(); return true; } if (d) { Throwable e = error; if (delayError) { if (empty) { if (e != null) { a.onError(e); } else { a.onComplete(); } worker.dispose(); return true; } } else { if (e != null) { queue.clear(); a.onError(e); worker.dispose(); return true; } else if (empty) { a.onComplete(); worker.dispose(); return true; } } } return false; } @Override public int requestFusion(int mode) { if ((mode & ASYNC) != 0) { outputFused = true; return ASYNC; } return NONE; } @Nullable @Override public T poll() throws Exception { return queue.poll(); } @Override public void clear() { queue.clear(); } @Override public boolean isEmpty() { return queue.isEmpty(); } } }