/**
* Copyright 2014 Netflix, 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 rx.internal.operators;
import rx.Observable;
import rx.Observable.Operator;
import rx.Producer;
import rx.Scheduler;
import rx.Scheduler.Worker;
import rx.Subscriber;
import rx.functions.Action0;
/**
* Subscribes Observers on the specified {@code Scheduler}.
* <p>
* <img width="640" src="https://github.com/Netflix/RxJava/wiki/images/rx-operators/subscribeOn.png" alt="">
*/
public class OperatorSubscribeOn<T> implements Operator<T, Observable<T>> {
private final Scheduler scheduler;
public OperatorSubscribeOn(Scheduler scheduler) {
this.scheduler = scheduler;
}
@Override
public Subscriber<? super Observable<T>> call(final Subscriber<? super T> subscriber) {
final Worker inner = scheduler.createWorker();
subscriber.add(inner);
return new Subscriber<Observable<T>>(subscriber) {
@Override
public void onCompleted() {
// ignore because this is a nested Observable and we expect only 1 Observable<T> emitted to onNext
}
@Override
public void onError(Throwable e) {
subscriber.onError(e);
}
@Override
public void onNext(final Observable<T> o) {
inner.schedule(new Action0() {
@Override
public void call() {
final Thread t = Thread.currentThread();
o.unsafeSubscribe(new Subscriber<T>(subscriber) {
@Override
public void onCompleted() {
subscriber.onCompleted();
}
@Override
public void onError(Throwable e) {
subscriber.onError(e);
}
@Override
public void onNext(T t) {
subscriber.onNext(t);
}
@Override
public void setProducer(final Producer producer) {
subscriber.setProducer(new Producer() {
@Override
public void request(final long n) {
if (Thread.currentThread() == t) {
// don't schedule if we're already on the thread (primarily for first setProducer call)
// see unit test 'testSetProducerSynchronousRequest' for more context on this
producer.request(n);
} else {
inner.schedule(new Action0() {
@Override
public void call() {
producer.request(n);
}
});
}
}
});
}
});
}
});
}
};
}
}