/**
* Copyright (c) 2016-present, RxJava Contributors.
*
* 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 io.reactivex.internal.operators.observable;
import io.reactivex.*;
import io.reactivex.disposables.Disposable;
import io.reactivex.internal.disposables.DisposableHelper;
public final class ObservableTakeLastOne<T> extends AbstractObservableWithUpstream<T, T> {
public ObservableTakeLastOne(ObservableSource<T> source) {
super(source);
}
@Override
public void subscribeActual(Observer<? super T> observer) {
source.subscribe(new TakeLastOneObserver<T>(observer));
}
static final class TakeLastOneObserver<T> implements Observer<T>, Disposable {
final Observer<? super T> downstream;
Disposableupstream;
T value;
TakeLastOneObserver(Observer<? super T> downstream) {
this.downstream = downstream;
}
@Override
public void onSubscribe(Disposabled) {
if (DisposableHelper.validate(this.upstream, d)) {
this.upstream = d;
downstream.onSubscribe(this);
}
}
@Override
public void onNext(T t) {
value = t;
}
@Override
public void onError(Throwablet) {
value = null;
downstream.onError(t);
}
@Override
public void onComplete() {
emit();
}
void emit() {
T v = value;
if (v != null) {
value = null;
downstream.onNext(v);
}
downstream.onComplete();
}
@Override
public void dispose() {
value = null;
upstream.dispose();
}
@Override
public boolean isDisposed() {
return upstream.isDisposed();
}
}
}