src/main/java/rx/internal/operators/OnSubscribeReduceSeed.java
/**
* Copyright 2016 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.OnSubscribe;
import rx.exceptions.Exceptions;
import rx.functions.Func2;
public final class OnSubscribeReduceSeed<T, R> implements OnSubscribe<R> {
final Observable<T> source;
final R initialValue;
final Func2<R, ? super T, R> reducer;
public OnSubscribeReduceSeed(Observable<T> source, R initialValue, Func2<R, ? super T, R> reducer) {
this.source = source;
this.initialValue = initialValue;
this.reducer = reducer;
}
@Override
public void call(Subscriber<? super R> t) {
new ReduceSeedSubscriber<T, R>(t, initialValue, reducer).subscribeTo(source);
}
static final class ReduceSeedSubscriber<T, R> extends DeferredScalarSubscriber<T, R> {
final Func2<R, ? super T, R> reducer;
public ReduceSeedSubscriber(Subscriber<? super R> actual, R initialValue, Func2<R, ? super T, R> reducer) {
super(actual);
this.value = initialValue;
this.hasValue = true;
this.reducer = reducer;
}
@Override
public void onNext(T t) {
try {
value = reducer.call(value, t);
} catch (Throwable ex) {
Exceptions.throwIfFatal(ex);
unsubscribe();
actual.onError(ex);
}
}
}
}