/**
* 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;
import rx.observers.*;
import rx.subjects.
PublishSubject;
/**
* Delay the subscription and emission of the source items by a per-item observable that fires its first element.
*
* @param <T>
* the item type
* @param <V>
* the value type of the item-delaying observable
*/
public final class
OperatorDelayWithSelector<T, V> implements
Operator<T, T> {
final
Observable<? extends T>
source;
final
Func1<? super T, ? extends
Observable<V>>
itemDelay;
public
OperatorDelayWithSelector(
Observable<? extends T>
source,
Func1<? super T, ? extends
Observable<V>>
itemDelay) {
this.
source =
source;
this.
itemDelay =
itemDelay;
}
@
Override
public
Subscriber<? super T>
call(final
Subscriber<? super T>
_child) {
final
SerializedSubscriber<T>
child = new
SerializedSubscriber<T>(
_child);
final
PublishSubject<
Observable<T>>
delayedEmissions =
PublishSubject.
create();
_child.
add(
Observable.
merge(
delayedEmissions).
unsafeSubscribe(
Subscribers.
from(
child)));
return new
Subscriber<T>(
_child) {
@
Override
public void
onCompleted() {
delayedEmissions.
onCompleted();
}
@
Override
public void
onError(
Throwable e) {
child.
onError(
e);
}
@
Override
public void
onNext(final T
t) {
try {
delayedEmissions.
onNext(
itemDelay.
call(
t).
take(1).
defaultIfEmpty(null).
map(new
Func1<V, T>() {
@
Override
public T
call(V
v) {
return
t;
}
}));
} catch (
Throwable e) {
Exceptions.
throwOrReport(
e, this);
}
}
};
}
}