/*
* 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.
Queue;
import java.util.function.
Supplier;
import reactor.core.
CoreSubscriber;
import reactor.core.
Fuseable;
import reactor.core.
Scannable;
import reactor.core.scheduler.
Scheduler;
import reactor.core.scheduler.
Scheduler.
Worker;
import reactor.util.annotation.
Nullable;
/**
* Ensures each 'rail' from upstream runs on a Worker from a Scheduler.
*
* @param <T> the value type
*/
final class
ParallelRunOn<T> extends
ParallelFlux<T> implements
Scannable{
final
ParallelFlux<? extends T>
source;
final
Scheduler scheduler;
final int
prefetch;
final
Supplier<
Queue<T>>
queueSupplier;
ParallelRunOn(
ParallelFlux<? extends T>
parent,
Scheduler scheduler, int
prefetch,
Supplier<
Queue<T>>
queueSupplier) {
if (
prefetch <= 0) {
throw new
IllegalArgumentException("prefetch > 0 required but it was " +
prefetch);
}
this.
source =
parent;
this.
scheduler =
scheduler;
this.
prefetch =
prefetch;
this.
queueSupplier =
queueSupplier;
}
@
Override
@
Nullable
public
Object scanUnsafe(
Attr key) {
if (
key ==
Attr.
PARENT) return
source;
if (
key ==
Attr.
PREFETCH) return
getPrefetch();
return null;
}
@
Override
@
SuppressWarnings("unchecked")
public void
subscribe(
CoreSubscriber<? super T>[]
subscribers) {
if (!
validate(
subscribers)) {
return;
}
int
n =
subscribers.length;
CoreSubscriber<T>[]
parents = new
CoreSubscriber[
n];
boolean
conditional =
subscribers[0] instanceof
Fuseable.
ConditionalSubscriber;
for (int
i = 0;
i <
n;
i++) {
Worker w =
scheduler.
createWorker();
if (
conditional) {
parents[
i] = new
FluxPublishOn.
PublishOnConditionalSubscriber<>(
(
Fuseable.
ConditionalSubscriber<T>)
subscribers[
i],
scheduler,
w, true,
prefetch,
prefetch,
queueSupplier);
}
else {
parents[
i] = new
FluxPublishOn.
PublishOnSubscriber<>(
subscribers[
i],
scheduler,
w, true,
prefetch,
prefetch,
queueSupplier);
}
}
source.
subscribe(
parents);
}
@
Override
public int
getPrefetch() {
return
prefetch;
}
@
Override
public int
parallelism() {
return
source.
parallelism();
}
}