/**
* 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.subjects;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
import static org.mockito.Matchers.any;
import static org.mockito.Mockito.inOrder;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.never;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import java.util.concurrent.*;
import java.util.concurrent.atomic.AtomicReference;
import org.junit.*;
import org.mockito.InOrder;
import org.mockito.Mockito;
import rx.*;
import rx.exceptions.CompositeException;
import rx.exceptions.OnErrorNotImplementedException;
import rx.exceptions.TestException;
import rx.functions.*;
import rx.observers.TestSubscriber;
import rx.schedulers.Schedulers;
public class BehaviorSubjectTest {
private final Throwable testException = new Throwable();
@Test
public void testThatObserverReceivesDefaultValueAndSubsequentEvents() {
BehaviorSubject<String> subject = BehaviorSubject.create("default");
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
subject.onNext("one");
subject.onNext("two");
subject.onNext("three");
verify(observer, times(1)).onNext("default");
verify(observer, times(1)).onNext("one");
verify(observer, times(1)).onNext("two");
verify(observer, times(1)).onNext("three");
verify(observer, Mockito.never()).onError(testException);
verify(observer, Mockito.never()).onCompleted();
}
@Test
public void testThatObserverReceivesLatestAndThenSubsequentEvents() {
BehaviorSubject<String> subject = BehaviorSubject.create("default");
subject.onNext("one");
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
subject.onNext("two");
subject.onNext("three");
verify(observer, Mockito.never()).onNext("default");
verify(observer, times(1)).onNext("one");
verify(observer, times(1)).onNext("two");
verify(observer, times(1)).onNext("three");
verify(observer, Mockito.never()).onError(testException);
verify(observer, Mockito.never()).onCompleted();
}
@Test
public void testSubscribeThenOnComplete() {
BehaviorSubject<String> subject = BehaviorSubject.create("default");
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
subject.onNext("one");
subject.onCompleted();
verify(observer, times(1)).onNext("default");
verify(observer, times(1)).onNext("one");
verify(observer, Mockito.never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
}
@Test
public void testSubscribeToCompletedOnlyEmitsOnComplete() {
BehaviorSubject<String> subject = BehaviorSubject.create("default");
subject.onNext("one");
subject.onCompleted();
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
verify(observer, never()).onNext("default");
verify(observer, never()).onNext("one");
verify(observer, Mockito.never()).onError(any(Throwable.class));
verify(observer, times(1)).onCompleted();
}
@Test
public void testSubscribeToErrorOnlyEmitsOnError() {
BehaviorSubject<String> subject = BehaviorSubject.create("default");
subject.onNext("one");
RuntimeException re = new RuntimeException("test error");
subject.onError(re);
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
verify(observer, never()).onNext("default");
verify(observer, never()).onNext("one");
verify(observer, times(1)).onError(re);
verify(observer, never()).onCompleted();
}
@Test
public void testCompletedStopsEmittingData() {
BehaviorSubject<Integer> channel = BehaviorSubject.create(2013);
@SuppressWarnings("unchecked")
Observer<Object> observerA = mock(Observer.class);
@SuppressWarnings("unchecked")
Observer<Object> observerB = mock(Observer.class);
@SuppressWarnings("unchecked")
Observer<Object> observerC = mock(Observer.class);
Subscription a = channel.subscribe(observerA);
channel.subscribe(observerB);
InOrder inOrderA = inOrder(observerA);
InOrder inOrderB = inOrder(observerB);
InOrder inOrderC = inOrder(observerC);
inOrderA.verify(observerA).onNext(2013);
inOrderB.verify(observerB).onNext(2013);
channel.onNext(42);
inOrderA.verify(observerA).onNext(42);
inOrderB.verify(observerB).onNext(42);
a.unsubscribe();
inOrderA.verifyNoMoreInteractions();
channel.onNext(4711);
inOrderB.verify(observerB).onNext(4711);
channel.onCompleted();
inOrderB.verify(observerB).onCompleted();
channel.subscribe(observerC);
inOrderC.verify(observerC).onCompleted();
channel.onNext(13);
inOrderB.verifyNoMoreInteractions();
inOrderC.verifyNoMoreInteractions();
}
@Test
public void testCompletedAfterErrorIsNotSent() {
BehaviorSubject<String> subject = BehaviorSubject.create("default");
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
subject.onNext("one");
subject.onError(testException);
subject.onNext("two");
subject.onCompleted();
verify(observer, times(1)).onNext("default");
verify(observer, times(1)).onNext("one");
verify(observer, times(1)).onError(testException);
verify(observer, never()).onNext("two");
verify(observer, never()).onCompleted();
}
@Test
public void testCompletedAfterErrorIsNotSent2() {
BehaviorSubject<String> subject = BehaviorSubject.create("default");
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
subject.onNext("one");
subject.onError(testException);
subject.onNext("two");
subject.onCompleted();
verify(observer, times(1)).onNext("default");
verify(observer, times(1)).onNext("one");
verify(observer, times(1)).onError(testException);
verify(observer, never()).onNext("two");
verify(observer, never()).onCompleted();
@SuppressWarnings("unchecked")
Observer<Object> o2 = mock(Observer.class);
subject.subscribe(o2);
verify(o2, times(1)).onError(testException);
verify(o2, never()).onNext(any());
verify(o2, never()).onCompleted();
}
@Test
public void testCompletedAfterErrorIsNotSent3() {
BehaviorSubject<String> subject = BehaviorSubject.create("default");
@SuppressWarnings("unchecked")
Observer<String> observer = mock(Observer.class);
subject.subscribe(observer);
subject.onNext("one");
subject.onCompleted();
subject.onNext("two");
subject.onCompleted();
verify(observer, times(1)).onNext("default");
verify(observer, times(1)).onNext("one");
verify(observer, times(1)).onCompleted();
verify(observer, never()).onError(any(Throwable.class));
verify(observer, never()).onNext("two");
@SuppressWarnings("unchecked")
Observer<Object> o2 = mock(Observer.class);
subject.subscribe(o2);
verify(o2, times(1)).onCompleted();
verify(o2, never()).onNext(any());
verify(observer, never()).onError(any(Throwable.class));
}
@Test(timeout = 1000)
public void testUnsubscriptionCase() {
BehaviorSubject<String> src = BehaviorSubject.create((String)null);
for (int i = 0; i < 10; i++) {
@SuppressWarnings("unchecked")
final Observer<Object> o = mock(Observer.class);
InOrder inOrder = inOrder(o);
String v = "" + i;
src.onNext(v);
System.out.printf("Turn: %d%n", i);
src.first()
.flatMap(new Func1<String, Observable<String>>() {
@Override
public Observable<String> call(String t1) {
return Observable.just(t1 + ", " + t1);
}
})
.subscribe(new Observer<String>() {
@Override
public void onNext(String t) {
o.onNext(t);
}
@Override
public void onError(Throwable e) {
o.onError(e);
}
@Override
public void onCompleted() {
o.onCompleted();
}
});
inOrder.verify(o).onNext(v + ", " + v);
inOrder.verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
}
}
@Test
public void testStartEmpty() {
BehaviorSubject<Integer> source = BehaviorSubject.create();
@SuppressWarnings("unchecked")
final Observer<Object> o = mock(Observer.class);
InOrder inOrder = inOrder(o);
source.subscribe(o);
inOrder.verify(o, never()).onNext(any());
inOrder.verify(o, never()).onCompleted();
source.onNext(1);
source.onCompleted();
source.onNext(2);
verify(o, never()).onError(any(Throwable.class));
inOrder.verify(o).onNext(1);
inOrder.verify(o).onCompleted();
inOrder.verifyNoMoreInteractions();
}
@Test
public void testStartEmptyThenAddOne() {
BehaviorSubject<Integer> source = BehaviorSubject.create();
@SuppressWarnings("unchecked")
final Observer<Object> o = mock(Observer.class);
InOrder inOrder = inOrder(o);
source.onNext(1);
source.subscribe(o);
inOrder.verify(o).onNext(1);
source.onCompleted();
source.onNext(2);
inOrder.verify(o).onCompleted();
inOrder.verifyNoMoreInteractions();
verify(o, never()).onError(any(Throwable.class));
}
@Test
public void testStartEmptyCompleteWithOne() {
BehaviorSubject<Integer> source = BehaviorSubject.create();
@SuppressWarnings("unchecked")
final Observer<Object> o = mock(Observer.class);
source.onNext(1);
source.onCompleted();
source.onNext(2);
source.subscribe(o);
verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
verify(o, never()).onNext(any());
}
@Test
public void testTakeOneSubscriber() {
BehaviorSubject<Integer> source = BehaviorSubject.create(1);
@SuppressWarnings("unchecked")
final Observer<Object> o = mock(Observer.class);
source.take(1).subscribe(o);
verify(o).onNext(1);
verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
assertEquals(0, source.subscriberCount());
assertFalse(source.hasObservers());
}
@Test
public void testOnErrorThrowsDoesntPreventDelivery() {
BehaviorSubject<String> ps = BehaviorSubject.create();
ps.subscribe();
TestSubscriber<String> ts = new TestSubscriber<String>();
ps.subscribe(ts);
try {
ps.onError(new RuntimeException("an exception"));
fail("expect OnErrorNotImplementedException");
} catch (OnErrorNotImplementedException e) {
// ignore
}
// even though the onError above throws we should still receive it on the other subscriber
assertEquals(1, ts.getOnErrorEvents().size());
}
/**
* This one has multiple failures so should get a CompositeException
*/
@Test
public void testOnErrorThrowsDoesntPreventDelivery2() {
BehaviorSubject<String> ps = BehaviorSubject.create();
ps.subscribe();
ps.subscribe();
TestSubscriber<String> ts = new TestSubscriber<String>();
ps.subscribe(ts);
ps.subscribe();
ps.subscribe();
ps.subscribe();
try {
ps.onError(new RuntimeException("an exception"));
fail("expect OnErrorNotImplementedException");
} catch (CompositeException e) {
// we should have 5 of them
assertEquals(5, e.getExceptions().size());
}
// even though the onError above throws we should still receive it on the other subscriber
assertEquals(1, ts.getOnErrorEvents().size());
}
@Test
public void testEmissionSubscriptionRace() throws Exception {
Scheduler s = Schedulers.io();
Scheduler.Worker worker = Schedulers.io().createWorker();
try {
for (int i = 0; i < 50000; i++) {
if (i % 1000 == 0) {
System.out.println(i);
}
final BehaviorSubject<Object> rs = BehaviorSubject.create();
final CountDownLatch finish = new CountDownLatch(1);
final CountDownLatch start = new CountDownLatch(1);
worker.schedule(new Action0() {
@Override
public void call() {
try {
start.await();
} catch (Exception e1) {
e1.printStackTrace();
}
rs.onNext(1);
}
});
final AtomicReference<Object> o = new AtomicReference<Object>();
rs.subscribeOn(s).observeOn(Schedulers.io())
.subscribe(new Observer<Object>() {
@Override
public void onCompleted() {
o.set(-1);
finish.countDown();
}
@Override
public void onError(Throwable e) {
o.set(e);
finish.countDown();
}
@Override
public void onNext(Object t) {
o.set(t);
finish.countDown();
}
});
start.countDown();
if (!finish.await(5, TimeUnit.SECONDS)) {
System.out.println(o.get());
System.out.println(rs.hasObservers());
rs.onCompleted();
Assert.fail("Timeout @ " + i);
break;
} else {
Assert.assertEquals(1, o.get());
worker.schedule(new Action0() {
@Override
public void call() {
rs.onCompleted();
}
});
}
}
} finally {
worker.unsubscribe();
}
}
@Test
public void testCurrentStateMethodsNormalEmptyStart() {
BehaviorSubject<Object> as = BehaviorSubject.create();
assertFalse(as.hasValue());
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertNull(as.getValue());
assertNull(as.getThrowable());
as.onNext(1);
assertTrue(as.hasValue());
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertEquals(1, as.getValue());
assertNull(as.getThrowable());
as.onCompleted();
assertFalse(as.hasValue());
assertFalse(as.hasThrowable());
assertTrue(as.hasCompleted());
assertNull(as.getValue());
assertNull(as.getThrowable());
}
@Test
public void testCurrentStateMethodsNormalSomeStart() {
BehaviorSubject<Object> as = BehaviorSubject.create((Object)1);
assertTrue(as.hasValue());
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertEquals(1, as.getValue());
assertNull(as.getThrowable());
as.onNext(2);
assertTrue(as.hasValue());
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertEquals(2, as.getValue());
assertNull(as.getThrowable());
as.onCompleted();
assertFalse(as.hasValue());
assertFalse(as.hasThrowable());
assertTrue(as.hasCompleted());
assertNull(as.getValue());
assertNull(as.getThrowable());
}
@Test
public void testCurrentStateMethodsEmpty() {
BehaviorSubject<Object> as = BehaviorSubject.create();
assertFalse(as.hasValue());
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertNull(as.getValue());
assertNull(as.getThrowable());
as.onCompleted();
assertFalse(as.hasValue());
assertFalse(as.hasThrowable());
assertTrue(as.hasCompleted());
assertNull(as.getValue());
assertNull(as.getThrowable());
}
@Test
public void testCurrentStateMethodsError() {
BehaviorSubject<Object> as = BehaviorSubject.create();
assertFalse(as.hasValue());
assertFalse(as.hasThrowable());
assertFalse(as.hasCompleted());
assertNull(as.getValue());
assertNull(as.getThrowable());
as.onError(new TestException());
assertFalse(as.hasValue());
assertTrue(as.hasThrowable());
assertFalse(as.hasCompleted());
assertNull(as.getValue());
assertTrue(as.getThrowable() instanceof TestException);
}
}