/*
* Copyright (c) 2011-2017 Pivotal Software Inc, 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
*
* 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 reactor.core.publisher;
import java.util.concurrent.atomic.
AtomicIntegerFieldUpdater;
import org.reactivestreams.
Publisher;
import reactor.core.
CoreSubscriber;
/**
* Repeatedly subscribes to the source and relays its values either
* indefinitely or a fixed number of times.
* <p>
* 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 <T> the value type
* @see <a href="https://github.com/reactor/reactive-streams-commons">Reactive-Streams-Commons</a>
*/
final class
FluxRepeat<T> extends
FluxOperator<T, T> {
final long
times;
FluxRepeat(
Flux<? extends T>
source, long
times) {
super(
source);
if (
times <= 0L) {
throw new
IllegalArgumentException("times > 0 required");
}
this.
times =
times;
}
@
Override
public void
subscribe(
CoreSubscriber<? super T>
actual) {
RepeatSubscriber<T>
parent = new
RepeatSubscriber<>(
source,
actual,
times + 1);
actual.
onSubscribe(
parent);
if (!
parent.
isCancelled()) {
parent.
onComplete();
}
}
static final class
RepeatSubscriber<T>
extends
Operators.
MultiSubscriptionSubscriber<T, T> {
final
Publisher<? extends T>
source;
long
remaining;
volatile int
wip;
@
SuppressWarnings("rawtypes")
static final
AtomicIntegerFieldUpdater<
RepeatSubscriber>
WIP =
AtomicIntegerFieldUpdater.
newUpdater(
RepeatSubscriber.class, "wip");
long
produced;
RepeatSubscriber(
Publisher<? extends T>
source,
CoreSubscriber<? super T>
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);
}
}
}
}