reactor.core.publisher.FluxRepeat Maven / Gradle / Ivy
Show all versions of redisson-all Show documentation
/*
* Copyright (c) 2016-2021 VMware Inc. or its affiliates, All Rights Reserved.
*
* 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
*
* https://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 reactor.core.publisher;
import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
import reactor.core.CorePublisher;
import reactor.core.CoreSubscriber;
/**
* Repeatedly subscribes to the source and relays its values either
* indefinitely or a fixed number of times.
*
* The times == Long.MAX_VALUE is treated as infinite repeat. Times = 1 mirrors the source
* (the "original" run) and then repeats it once more. Callers should take care of times =
* 0 and times = -1 cases, which should map to replaying the source and an empty sequence,
* respectively.
*
* @param the value type
* @see Reactive-Streams-Commons
*/
final class FluxRepeat extends InternalFluxOperator {
final long times;
FluxRepeat(Flux source, long times) {
super(source);
if (times <= 0L) {
throw new IllegalArgumentException("times > 0 required");
}
this.times = times;
}
@Override
public CoreSubscriber subscribeOrReturn(CoreSubscriber actual) {
RepeatSubscriber parent = new RepeatSubscriber<>(source, actual, times + 1);
actual.onSubscribe(parent);
if (!parent.isCancelled()) {
parent.onComplete();
}
return null;
}
@Override
public Object scanUnsafe(Attr key) {
if (key == Attr.RUN_STYLE) return Attr.RunStyle.SYNC;
return super.scanUnsafe(key);
}
static final class RepeatSubscriber
extends Operators.MultiSubscriptionSubscriber {
final CorePublisher source;
long remaining;
volatile int wip;
@SuppressWarnings("rawtypes")
static final AtomicIntegerFieldUpdater WIP =
AtomicIntegerFieldUpdater.newUpdater(RepeatSubscriber.class, "wip");
long produced;
RepeatSubscriber(CorePublisher source, CoreSubscriber actual, long remaining) {
super(actual);
this.source = source;
this.remaining = remaining;
}
@Override
public void onNext(T t) {
produced++;
actual.onNext(t);
}
@Override
public void onComplete() {
long r = remaining;
if (r != Long.MAX_VALUE) {
if (r == 0) {
actual.onComplete();
return;
}
remaining = r - 1;
}
resubscribe();
}
void resubscribe() {
if (WIP.getAndIncrement(this) == 0) {
do {
if (isCancelled()) {
return;
}
long c = produced;
if (c != 0L) {
produced = 0L;
produced(c);
}
source.subscribe(this);
} while (WIP.decrementAndGet(this) != 0);
}
}
@Override
public Object scanUnsafe(Attr key) {
if (key == Attr.RUN_STYLE) return Attr.RunStyle.SYNC;
return super.scanUnsafe(key);
}
}
}