/** * 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.*; import java.util.concurrent.Callable; import java.util.concurrent.atomic.*; import org.reactivestreams.*; import io.reactivex.*; import io.reactivex.exceptions.Exceptions; import io.reactivex.functions.BooleanSupplier; import io.reactivex.internal.functions.ObjectHelper; import io.reactivex.internal.subscriptions.SubscriptionHelper; import io.reactivex.internal.util.*; import io.reactivex.plugins.RxJavaPlugins; public final class FlowableBuffer<T, C extends Collection<? super T>> extends AbstractFlowableWithUpstream<T, C> { final int size; final int skip; final Callable<C> bufferSupplier; public FlowableBuffer(Flowable<T> source, int size, int skip, Callable<C> bufferSupplier) { super(source); this.size = size; this.skip = skip; this.bufferSupplier = bufferSupplier; } @Override public void subscribeActual(Subscriber<? super C> s) { if (size == skip) { source.subscribe(new PublisherBufferExactSubscriber<T, C>(s, size, bufferSupplier)); } else if (skip > size) { source.subscribe(new PublisherBufferSkipSubscriber<T, C>(s, size, skip, bufferSupplier)); } else { source.subscribe(new PublisherBufferOverlappingSubscriber<T, C>(s, size, skip, bufferSupplier)); } } static final class PublisherBufferExactSubscriber<T, C extends Collection<? super T>> implements FlowableSubscriber<T>, Subscription { final Subscriber<? super C> actual; final Callable<C> bufferSupplier; final int size; C buffer; Subscription s; boolean done; int index; PublisherBufferExactSubscriber(Subscriber<? super C> actual, int size, Callable<C> bufferSupplier) { this.actual = actual; this.size = size; this.bufferSupplier = bufferSupplier; } @Override public void request(long n) { if (SubscriptionHelper.validate(n)) { s.request(BackpressureHelper.multiplyCap(n, size)); } } @Override public void cancel() { s.cancel(); } @Override public void onSubscribe(Subscription s) { if (SubscriptionHelper.validate(this.s, s)) { this.s = s; actual.onSubscribe(this); } } @Override public void onNext(T t) { if (done) { return; } C b = buffer; if (b == null) { try { b = ObjectHelper.requireNonNull(bufferSupplier.call(), "The bufferSupplier returned a null buffer"); } catch (Throwable e) { Exceptions.throwIfFatal(e); cancel(); onError(e); return; } buffer = b; } b.add(t); int i = index + 1; if (i == size) { index = 0; buffer = null; actual.onNext(b); } else { index = i; } } @Override public void onError(Throwable t) { if (done) { RxJavaPlugins.onError(t); return; } done = true; actual.onError(t); } @Override public void onComplete() { if (done) { return; } done = true; C b = buffer; if (b != null && !b.isEmpty()) { actual.onNext(b); } actual.onComplete(); } } static final class PublisherBufferSkipSubscriber<T, C extends Collection<? super T>> extends AtomicInteger implements FlowableSubscriber<T>, Subscription { private static final long serialVersionUID = -5616169793639412593L; final Subscriber<? super C> actual; final Callable<C> bufferSupplier; final int size; final int skip; C buffer; Subscription s; boolean done; int index; PublisherBufferSkipSubscriber(Subscriber<? super C> actual, int size, int skip, Callable<C> bufferSupplier) { this.actual = actual; this.size = size; this.skip = skip; this.bufferSupplier = bufferSupplier; } @Override public void request(long n) { if (SubscriptionHelper.validate(n)) { if (get() == 0 && compareAndSet(0, 1)) { // n full buffers long u = BackpressureHelper.multiplyCap(n, size); // + (n - 1) gaps long v = BackpressureHelper.multiplyCap(skip - size, n - 1); s.request(BackpressureHelper.addCap(u, v)); } else { // n full buffer + gap s.request(BackpressureHelper.multiplyCap(skip, n)); } } } @Override public void cancel() { s.cancel(); } @Override public void onSubscribe(Subscription s) { if (SubscriptionHelper.validate(this.s, s)) { this.s = s; actual.onSubscribe(this); } } @Override public void onNext(T t) { if (done) { return; } C b = buffer; int i = index; if (i++ == 0) { try { b = ObjectHelper.requireNonNull(bufferSupplier.call(), "The bufferSupplier returned a null buffer"); } catch (Throwable e) { Exceptions.throwIfFatal(e); cancel(); onError(e); return; } buffer = b; } if (b != null) { b.add(t); if (b.size() == size) { buffer = null; actual.onNext(b); } } if (i == skip) { i = 0; } index = i; } @Override public void onError(Throwable t) { if (done) { RxJavaPlugins.onError(t); return; } done = true; buffer = null; actual.onError(t); } @Override public void onComplete() { if (done) { return; } done = true; C b = buffer; buffer = null; if (b != null) { actual.onNext(b); } actual.onComplete(); } } static final class PublisherBufferOverlappingSubscriber<T, C extends Collection<? super T>> extends AtomicLong implements FlowableSubscriber<T>, Subscription, BooleanSupplier { private static final long serialVersionUID = -7370244972039324525L; final Subscriber<? super C> actual; final Callable<C> bufferSupplier; final int size; final int skip; final ArrayDeque<C> buffers; final AtomicBoolean once; Subscription s; boolean done; int index; volatile boolean cancelled; long produced; PublisherBufferOverlappingSubscriber(Subscriber<? super C> actual, int size, int skip, Callable<C> bufferSupplier) { this.actual = actual; this.size = size; this.skip = skip; this.bufferSupplier = bufferSupplier; this.once = new AtomicBoolean(); this.buffers = new ArrayDeque<C>(); } @Override public boolean getAsBoolean() { return cancelled; } @Override public void request(long n) { if (SubscriptionHelper.validate(n)) { if (QueueDrainHelper.postCompleteRequest(n, actual, buffers, this, this)) { return; } if (!once.get() && once.compareAndSet(false, true)) { // (n - 1) skips long u = BackpressureHelper.multiplyCap(skip, n - 1); // + 1 full buffer long r = BackpressureHelper.addCap(size, u); s.request(r); } else { // n skips long r = BackpressureHelper.multiplyCap(skip, n); s.request(r); } } } @Override public void cancel() { cancelled = true; s.cancel(); } @Override public void onSubscribe(Subscription s) { if (SubscriptionHelper.validate(this.s, s)) { this.s = s; actual.onSubscribe(this); } } @Override public void onNext(T t) { if (done) { return; } ArrayDeque<C> bs = buffers; int i = index; if (i++ == 0) { C b; try { b = ObjectHelper.requireNonNull(bufferSupplier.call(), "The bufferSupplier returned a null buffer"); } catch (Throwable e) { Exceptions.throwIfFatal(e); cancel(); onError(e); return; } bs.offer(b); } C b = bs.peek(); if (b != null && b.size() + 1 == size) { bs.poll(); b.add(t); produced++; actual.onNext(b); } for (C b0 : bs) { b0.add(t); } if (i == skip) { i = 0; } index = i; } @Override public void onError(Throwable t) { if (done) { RxJavaPlugins.onError(t); return; } done = true; buffers.clear(); actual.onError(t); } @Override public void onComplete() { if (done) { return; } done = true; long p = produced; if (p != 0L) { BackpressureHelper.produced(this, p); } QueueDrainHelper.postComplete(actual, buffers, this, this); } } }