reactor.rx.stream.PublisherStream Maven / Gradle / Ivy
/*
* Copyright (c) 2011-2014 Pivotal Software, Inc.
*
* 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.rx.stream;
import org.reactivestreams.Publisher;
import org.reactivestreams.Subscriber;
import org.reactivestreams.Subscription;
import reactor.core.support.Exceptions;
import reactor.rx.Stream;
import reactor.rx.subscription.ReactiveSubscription;
/**
* A {@link org.reactivestreams.Publisher} wrapper that takes care of lazy subscribing.
*
* The stream will directly forward all the signals passed to the subscribers and complete when onComplete is called.
*
* Create such stream with the provided factory, E.g.:
*
* {@code
* Streams.create(sub -> sub.onNext(1))
* }
*
*
* @author Stephane Maldini
*/
public class PublisherStream extends Stream {
private final Publisher source;
public PublisherStream(Publisher publisher) {
this.source = publisher;
}
@Override
public void subscribe(final Subscriber subscriber) {
try {
subscriber.onSubscribe(new ReactiveSubscription(PublisherStream.this, subscriber) {
private boolean started = false;
private ReactiveSubscription thiz = this;
private Subscription subscription;
@Override
protected void onRequest(long elements) {
super.onRequest(elements);
if (!started) {
started = true;
source.subscribe(new Subscriber() {
@Override
public void onSubscribe(Subscription s) {
subscription = s;
}
@Override
public void onNext(T t) {
thiz.onNext(t);
}
@Override
public void onError(Throwable t) {
thiz.onError(t);
}
@Override
public void onComplete() {
thiz.onComplete();
}
});
} else if (subscription != null) {
subscription.request(elements);
}
}
@Override
public void cancel() {
super.cancel();
if (subscription != null) {
subscription.cancel();
}
}
});
} catch (Throwable throwable) {
Exceptions.throwIfFatal(throwable);
subscriber.onError(throwable);
}
}
}