/**
* 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 java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import org.junit.Test;
import rx.Observable;
import rx.Observable.OnSubscribe;
import rx.Observer;
import rx.Subscriber;
import rx.Subscription;
import rx.exceptions.MissingBackpressureException;
import rx.functions.Action0;
import rx.observers.TestSubscriber;
import rx.schedulers.Schedulers;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
public class OperatorOnBackpressureBufferTest {
@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 = 2000)
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()).onBackpressureBuffer().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());
assertEquals(499, ts.getOnNextEvents().get(499).intValue());
}
@Test(expected = IllegalArgumentException.class)
public void testFixBackpressureBufferNegativeCapacity() throws InterruptedException {
Observable.empty().onBackpressureBuffer(-1);
}
@Test(expected = IllegalArgumentException.class)
public void testFixBackpressureBufferZeroCapacity() throws InterruptedException {
Observable.empty().onBackpressureBuffer(0);
}
@Test
public void testFixBackpressureBoundedBuffer() throws InterruptedException {
final CountDownLatch l1 = new CountDownLatch(100);
final CountDownLatch backpressureCallback = new CountDownLatch(1);
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();
}
});
ts.requestMore(100);
Subscription s = infinite.subscribeOn(Schedulers.computation())
.onBackpressureBuffer(500, new Action0() {
@Override
public void call() {
backpressureCallback.countDown();
}
}).take(1000).subscribe(ts);
l1.await();
ts.requestMore(50);
assertTrue(backpressureCallback.await(500, TimeUnit.MILLISECONDS));
assertTrue(ts.getOnErrorEvents().get(0) instanceof MissingBackpressureException);
int size = ts.getOnNextEvents().size();
assertTrue(size <= 150); // will get up to 50 more
assertTrue(ts.getOnNextEvents().get(size-1) == size-1);
assertTrue(s.isUnsubscribed());
}
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++);
}
}
});
}