/**
* 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 java.util.concurrent.
TimeUnit;
import java.util.concurrent.atomic.*;
import io.reactivex.*;
import io.reactivex.disposables.
Disposable;
import io.reactivex.internal.disposables.
DisposableHelper;
import io.reactivex.observers.
SerializedObserver;
public final class
ObservableSampleTimed<T> extends
AbstractObservableWithUpstream<T, T> {
final long
period;
final
TimeUnit unit;
final
Scheduler scheduler;
final boolean
emitLast;
public
ObservableSampleTimed(
ObservableSource<T>
source, long
period,
TimeUnit unit,
Scheduler scheduler, boolean
emitLast) {
super(
source);
this.
period =
period;
this.
unit =
unit;
this.
scheduler =
scheduler;
this.
emitLast =
emitLast;
}
@
Override
public void
subscribeActual(
Observer<? super T>
t) {
SerializedObserver<T>
serial = new
SerializedObserver<T>(
t);
if (
emitLast) {
source.
subscribe(new
SampleTimedEmitLast<T>(
serial,
period,
unit,
scheduler));
} else {
source.
subscribe(new
SampleTimedNoLast<T>(
serial,
period,
unit,
scheduler));
}
}
abstract static class
SampleTimedObserver<T> extends
AtomicReference<T> implements
Observer<T>,
Disposable,
Runnable {
private static final long
serialVersionUID = -3517602651313910099L;
final
Observer<? super T>
downstream;
final long
period;
final
TimeUnit unit;
final
Scheduler scheduler;
final
AtomicReference<
Disposable>
timer = new
AtomicReference<
Disposable>();
Disposable upstream;
SampleTimedObserver(
Observer<? super T>
actual, long
period,
TimeUnit unit,
Scheduler scheduler) {
this.
downstream =
actual;
this.
period =
period;
this.
unit =
unit;
this.
scheduler =
scheduler;
}
@
Override
public void
onSubscribe(
Disposable d) {
if (
DisposableHelper.
validate(this.
upstream,
d)) {
this.
upstream =
d;
downstream.
onSubscribe(this);
Disposable task =
scheduler.
schedulePeriodicallyDirect(this,
period,
period,
unit);
DisposableHelper.
replace(
timer,
task);
}
}
@
Override
public void
onNext(T
t) {
lazySet(
t);
}
@
Override
public void
onError(
Throwable t) {
cancelTimer();
downstream.
onError(
t);
}
@
Override
public void
onComplete() {
cancelTimer();
complete();
}
void
cancelTimer() {
DisposableHelper.
dispose(
timer);
}
@
Override
public void
dispose() {
cancelTimer();
upstream.
dispose();
}
@
Override
public boolean
isDisposed() {
return
upstream.
isDisposed();
}
void
emit() {
T
value =
getAndSet(null);
if (
value != null) {
downstream.
onNext(
value);
}
}
abstract void
complete();
}
static final class
SampleTimedNoLast<T> extends
SampleTimedObserver<T> {
private static final long
serialVersionUID = -7139995637533111443L;
SampleTimedNoLast(
Observer<? super T>
actual, long
period,
TimeUnit unit,
Scheduler scheduler) {
super(
actual,
period,
unit,
scheduler);
}
@
Override
void
complete() {
downstream.
onComplete();
}
@
Override
public void
run() {
emit();
}
}
static final class
SampleTimedEmitLast<T> extends
SampleTimedObserver<T> {
private static final long
serialVersionUID = -7139995637533111443L;
final
AtomicInteger wip;
SampleTimedEmitLast(
Observer<? super T>
actual, long
period,
TimeUnit unit,
Scheduler scheduler) {
super(
actual,
period,
unit,
scheduler);
this.
wip = new
AtomicInteger(1);
}
@
Override
void
complete() {
emit();
if (
wip.
decrementAndGet() == 0) {
downstream.
onComplete();
}
}
@
Override
public void
run() {
if (
wip.
incrementAndGet() == 2) {
emit();
if (
wip.
decrementAndGet() == 0) {
downstream.
onComplete();
}
}
}
}
}