rx.internal.operators.OperatorTakeUntilPredicate Maven / Gradle / Ivy
/**
* 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.*;
import rx.Observable.Operator;
import rx.exceptions.Exceptions;
import rx.functions.Func1;
/**
* Returns an Observable that emits items emitted by the source Observable until
* the provided predicate returns false
*
* @param the value type
*/
public final class OperatorTakeUntilPredicate implements Operator {
final Func1 stopPredicate;
public OperatorTakeUntilPredicate(final Func1 stopPredicate) {
this.stopPredicate = stopPredicate;
}
@Override
public Subscriber call(final Subscriber child) {
final ParentSubscriber parent = new ParentSubscriber(child);
child.add(parent); // don't unsubscribe downstream
child.setProducer(new Producer() {
@Override
public void request(long n) {
parent.downstreamRequest(n);
}
});
return parent;
}
/** Subscriber returned to the upstream. */
final class ParentSubscriber extends Subscriber {
private final Subscriber child;
private boolean done;
ParentSubscriber(Subscriber child) {
this.child = child;
}
@Override
public void onNext(T t) {
child.onNext(t);
boolean stop;
try {
stop = stopPredicate.call(t);
} catch (Throwable e) {
done = true;
Exceptions.throwOrReport(e, child, t);
unsubscribe();
return;
}
if (stop) {
done = true;
child.onCompleted();
unsubscribe();
}
}
@Override
public void onCompleted() {
if (!done) {
child.onCompleted();
}
}
@Override
public void onError(Throwable e) {
if (!done) {
child.onError(e);
}
}
void downstreamRequest(long n) {
request(n);
}
}
}