/**
* 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 static org.junit.Assert.assertEquals;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicInteger;
import org.junit.Test;
import rx.Observable;
import rx.Observable.OnSubscribe;
import rx.Observer;
import rx.Subscriber;
import rx.internal.util.RxRingBuffer;
import rx.observers.TestSubscriber;
import rx.schedulers.Schedulers;
public class OperatorOnBackpressureDropTest {
@Test
public void testNoBackpressureSupport() {
TestSubscriber<Long> ts = new TestSubscriber<Long>();
// this will be ignored
ts.requestMore(100);
// we take 500 so it unsubscribes
infinite.take(500).subscribe(ts);
// it completely ignores the `request(100)` and we get 500
assertEquals(500, ts.getOnNextEvents().size());
ts.assertNoErrors();
}
@Test(timeout = 500)
public void testWithObserveOn() throws InterruptedException {
TestSubscriber<Integer> ts = new TestSubscriber<Integer>();
Observable.range(0, RxRingBuffer.SIZE * 10).onBackpressureDrop().observeOn(Schedulers.io()).subscribe(ts);
ts.awaitTerminalEvent();
}
@Test(timeout = 500)
public void testFixBackpressureWithBuffer() throws InterruptedException {
final CountDownLatch l1 = new CountDownLatch(100);
final CountDownLatch l2 = new CountDownLatch(150);
TestSubscriber<Long> ts = new TestSubscriber<Long>(new Observer<Long>() {
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
}
@Override
public void onNext(Long t) {
l1.countDown();
l2.countDown();
}
});
// this will be ignored
ts.requestMore(100);
// we take 500 so it unsubscribes
infinite.subscribeOn(Schedulers.computation()).onBackpressureDrop().take(500).subscribe(ts);
// it completely ignores the `request(100)` and we get 500
l1.await();
assertEquals(100, ts.getOnNextEvents().size());
ts.requestMore(50);
l2.await();
assertEquals(150, ts.getOnNextEvents().size());
ts.requestMore(350);
ts.awaitTerminalEvent();
assertEquals(500, ts.getOnNextEvents().size());
ts.assertNoErrors();
assertEquals(0, ts.getOnNextEvents().get(0).intValue());
}
@Test
public void testRequestOverflow() throws InterruptedException {
final AtomicInteger count = new AtomicInteger();
int n = 10;
range(n).onBackpressureDrop().subscribe(new Subscriber<Long>() {
@Override
public void onStart() {
request(10);
}
@Override
public void onCompleted() {
}
@Override
public void onError(Throwable e) {
throw new RuntimeException(e);
}
@Override
public void onNext(Long t) {
count.incrementAndGet();
//cause overflow of requested if not handled properly in onBackpressureDrop operator
request(Long.MAX_VALUE-1);
}});
assertEquals(n, count.get());
}
static final Observable<Long> infinite = Observable.create(new OnSubscribe<Long>() {
@Override
public void call(Subscriber<? super Long> s) {
long i = 0;
while (!s.isUnsubscribed()) {
s.onNext(i++);
}
}
});
private static final Observable<Long> range(final long n) {
return Observable.create(new OnSubscribe<Long>() {
@Override
public void call(Subscriber<? super Long> s) {
for (long i=0;i < n;i++) {
if (s.isUnsubscribed()) {
break;
}
s.onNext(i);
}
s.onCompleted();
}
});
}
}