Java Code Examples for rx.subjects.BehaviorSubject#onNext()

@Test
public void testMany() {
    BehaviorSubject<List<Integer>> source = BehaviorSubject.create();
    LoadBalancer<Integer> lb = LoadBalancer.fromSnapshotSource(source).build(ChoiceOfTwoLoadBalancer.create(COMPARATOR));
    
    source.onNext(Lists.newArrayList(0,1,2,3,4,5,6,7,8,9));
    
    AtomicIntegerArray counts = new AtomicIntegerArray(10);
    
    for (int i = 0; i < 100000; i++) {
        counts.incrementAndGet(lb.next());
    }
    Double[] pct = new Double[counts.length()];
    for (int i = 0; i < counts.length(); i++) {
        pct[i] = counts.get(i)/100000.0;
    }
    
    for (int i = 1; i < counts.length(); i++) {
        Assert.assertTrue(counts.get(i) > counts.get(i-1));
    }
}
 

@Override
public void addToPlaylist(Playlist playlist, Song song) {
    MediaStoreUtil.appendToPlaylist(mContext, playlist, song);

    if (mPlaylistContents.containsKey(playlist)) {
        BehaviorSubject<List<Song>> observableContents = mPlaylistContents.get(playlist);
        List<Song> updatedContents = new ArrayList<>(observableContents.getValue());
        updatedContents.add(song);
        observableContents.onNext(updatedContents);
    }
}
 

@Override
public void addToPlaylist(Playlist playlist, List<Song> songs) {
    MediaStoreUtil.appendToPlaylist(mContext, playlist, songs);

    if (mPlaylistContents.containsKey(playlist)) {
        BehaviorSubject<List<Song>> observableContents = mPlaylistContents.get(playlist);
        List<Song> updatedContents = new ArrayList<>(observableContents.getValue());
        updatedContents.addAll(songs);
        observableContents.onNext(updatedContents);
    }
}
 

@Test
public void testOne() {
    BehaviorSubject<List<Integer>> source = BehaviorSubject.create();
    LoadBalancer<Integer> lb = LoadBalancer.fromSnapshotSource(source).build(ChoiceOfTwoLoadBalancer.create(COMPARATOR));
    
    source.onNext(Lists.newArrayList(0));

    for (int i = 0; i < 100; i++) {
        Assert.assertEquals(0, (int)lb.next());
    }
}
 

@Test
public void testTwo() {
    BehaviorSubject<List<Integer>> source = BehaviorSubject.create();
    LoadBalancer<Integer> lb = LoadBalancer.fromSnapshotSource(source).build(ChoiceOfTwoLoadBalancer.create(COMPARATOR));
    
    source.onNext(Lists.newArrayList(0,1));
    
    AtomicIntegerArray counts = new AtomicIntegerArray(2);
    
    for (int i = 0; i < 100; i++) {
        counts.incrementAndGet(lb.next());
    }
    Assert.assertEquals(counts.get(0), 0);
    Assert.assertEquals(counts.get(1), 100);
}
 

@Test
public void testPagingCapabilities() {
    PublishSubject<Object> view = PublishSubject.create();
    BehaviorSubject<Integer> nextPageRequests = BehaviorSubject.create();
    final TestObserver<Delivery<Object, String>> testObserver = new TestObserver<>();

    nextPageRequests
        .concatMap(new Func1<Integer, Observable<Integer>>() {
            @Override
            public Observable<Integer> call(Integer targetPage) {
                return targetPage <= requestedPageCount ?
                    Observable.<Integer>never() :
                    Observable.range(requestedPageCount, targetPage - requestedPageCount);
            }
        })
        .doOnNext(new Action1<Integer>() {
            @Override
            public void call(Integer it) {
                requestedPageCount = it + 1;
            }
        })
        .startWith(Observable.range(0, requestedPageCount))
        .concatMap(new Func1<Integer, Observable<String>>() {
            @Override
            public Observable<String> call(final Integer page) {
                return requestPage(page, PAGE_SIZE);
            }
        })
        .compose(new DeliverReplay<Object, String>(view))
        .subscribe(testObserver);

    ArrayList<Delivery<Object, String>> onNext = new ArrayList<>();

    testObserver.assertReceivedOnNext(onNext);

    view.onNext(999);
    addOnNext(onNext, 999, 0, 1, 2);

    testObserver.assertReceivedOnNext(onNext);

    nextPageRequests.onNext(2);
    addOnNext(onNext, 999, 3, 4, 5);

    testObserver.assertReceivedOnNext(onNext);

    view.onNext(null);

    assertEquals(0, testObserver.getOnCompletedEvents().size());
    testObserver.assertReceivedOnNext(onNext);

    nextPageRequests.onNext(3);

    assertEquals(0, testObserver.getOnCompletedEvents().size());
    testObserver.assertReceivedOnNext(onNext);

    view.onNext(9999);
    addOnNext(onNext, 9999, 0, 1, 2, 3, 4, 5, 6, 7, 8);

    assertEquals(0, testObserver.getOnCompletedEvents().size());
    testObserver.assertReceivedOnNext(onNext);
}
 

@Test
public void behaviorSubjectSubscribeHeartbeat() throws Exception {
    final List<String> events = newArrayList(
        SUBSCRIBED,
        HEARTBEAT
    );
    final List<byte[]> expected = events.stream()
        .map(StringMessageCodec.UTF8_STRING::encode)
        .map(RecordIOUtils::createChunk)
        .collect(Collectors.toList());

    /*
     * Use of BehaviorSubject here is important. The reason is that BehaviorSubject will buffer any items passed
     * to it's onNext method even if the Subject has not yet been subscribed to. A PublishSubject will only forward
     * events to it's subscriber without any buffering.
     */
    final BehaviorSubject<String> subject = BehaviorSubject.create();
    final MesosServerSimulation<String, String> sim = new MesosServerSimulation<>(
        Observable.from(events),
        StringMessageCodec.UTF8_STRING,
        StringMessageCodec.UTF8_STRING,
        SUBSCRIBE::equals
    );
    final int serverPort = sim.start();
    final URI uri = URI.create(String.format("http://localhost:%d/api/v1/scheduler", serverPort));
    final HttpClient<ByteBuf, ByteBuf> httpClient = createClient(uri);
    final HttpClientRequest<ByteBuf> request = createRequest(uri, SUBSCRIBE);

    final Observable<byte[]> observable = openStream(httpClient, request);

    final TestSubscriber<byte[]> testSubscriber = new TestSubscriber<>();
    final AwaitableEventSubscriberDecorator<byte[]> sub = new AwaitableEventSubscriberDecorator<>(testSubscriber);

    assertThat(sim.getCallsReceived()).hasSize(0);
    assertThat(testSubscriber.getOnNextEvents()).hasSize(0);

    final Subscription subscription = observable.subscribe(sub);

    // SUBSCRIBED
    subject.onNext(events.get(0));

    // HEARTBEAT
    subject.onNext(events.get(1));
    sub.awaitEvent(2);
    final List<byte[]> onNextEvents = testSubscriber.getOnNextEvents();
    assertThat(onNextEvents).hasSize(2);
    assertThat(onNextEvents.get(0)).isEqualTo(expected.get(0));
    assertThat(onNextEvents.get(1)).isEqualTo(expected.get(1));

    assertThat(sim.getCallsReceived()).hasSize(1);
    assertThat(sim.getCallsReceived()).contains(SUBSCRIBE);
    assertThat(deepEquals(expected, testSubscriber.getOnNextEvents())).isTrue();
    subscription.unsubscribe();
    sim.shutdown();
}
 

@Test
public void testPagingCapabilities() {
    PublishSubject<Object> view = PublishSubject.create();
    BehaviorSubject<Integer> nextPageRequests = BehaviorSubject.create();
    final TestObserver<Delivery<Object, String>> testObserver = new TestObserver<>();

    nextPageRequests
        .concatMap(new Func1<Integer, Observable<Integer>>() {
            @Override
            public Observable<Integer> call(Integer targetPage) {
                return targetPage <= requestedPageCount ?
                    Observable.<Integer>never() :
                    Observable.range(requestedPageCount, targetPage - requestedPageCount);
            }
        })
        .doOnNext(new Action1<Integer>() {
            @Override
            public void call(Integer it) {
                requestedPageCount = it + 1;
            }
        })
        .startWith(Observable.range(0, requestedPageCount))
        .concatMap(new Func1<Integer, Observable<String>>() {
            @Override
            public Observable<String> call(final Integer page) {
                return requestPage(page, PAGE_SIZE);
            }
        })
        .compose(new DeliverReplay<Object, String>(view))
        .subscribe(testObserver);

    ArrayList<Delivery<Object, String>> onNext = new ArrayList<>();

    testObserver.assertReceivedOnNext(onNext);

    view.onNext(999);
    addOnNext(onNext, 999, 0, 1, 2);

    testObserver.assertReceivedOnNext(onNext);

    nextPageRequests.onNext(2);
    addOnNext(onNext, 999, 3, 4, 5);

    testObserver.assertReceivedOnNext(onNext);

    view.onNext(null);

    assertEquals(0, testObserver.getOnCompletedEvents().size());
    testObserver.assertReceivedOnNext(onNext);

    nextPageRequests.onNext(3);

    assertEquals(0, testObserver.getOnCompletedEvents().size());
    testObserver.assertReceivedOnNext(onNext);

    view.onNext(9999);
    addOnNext(onNext, 9999, 0, 1, 2, 3, 4, 5, 6, 7, 8);

    assertEquals(0, testObserver.getOnCompletedEvents().size());
    testObserver.assertReceivedOnNext(onNext);
}
 

@Test(expected=NoSuchElementException.class)
public void testEmpty() {
    BehaviorSubject<List<Integer>> source = BehaviorSubject.create();
    
    LoadBalancer<Integer> lb = LoadBalancer.fromSnapshotSource(source).build(ChoiceOfTwoLoadBalancer.create(COMPARATOR));
    
    source.onNext(Lists.<Integer>newArrayList());
    
    lb.next();
}