BlockingOperatorMostRecent { public static <T> Iterable<T> mostRecent(final Observable<? extends T> source, final T initialValue) { return new Iterable<T>() { @Override public Iterator<T> iterator() { MostRecentObserver<T> mostRecentObserver = new MostRecentObserver<T>(initialValue); source.subscribe(mostRecentObserver); return mostRecentObserver.getIterable(); } }; } private  BlockingOperatorMostRecent(); static Iterable<T> mostRecent(final Observable<? extends T> source, final T initialValue);  }
@Test public void testMostRecentNull() { assertEquals(null, Observable.<Void>never().toBlocking().mostRecent(null).iterator().next()); }
@Test public void testMostRecent() { Subject<String, String> s = PublishSubject.create(); Iterator<String> it = mostRecent(s, "default").iterator(); assertTrue(it.hasNext()); assertEquals("default", it.next()); assertEquals("default", it.next()); s.onNext("one"); assertTrue(it.hasNext()); assertEquals("one", it.next()); assertEquals("one", it.next()); s.onNext("two"); assertTrue(it.hasNext()); assertEquals("two", it.next()); assertEquals("two", it.next()); s.onCompleted(); assertFalse(it.hasNext()); }
@Test(expected = TestException.class) public void testMostRecentWithException() { Subject<String, String> s = PublishSubject.create(); Iterator<String> it = mostRecent(s, "default").iterator(); assertTrue(it.hasNext()); assertEquals("default", it.next()); assertEquals("default", it.next()); s.onError(new TestException()); assertTrue(it.hasNext()); it.next(); }
@Test(timeout = 1000) public void testSingleSourceManyIterators() { TestScheduler scheduler = new TestScheduler(); BlockingObservable<Long> source = Observable.interval(1, TimeUnit.SECONDS, scheduler).take(10).toBlocking(); Iterable<Long> iter = source.mostRecent(-1L); for (int j = 0; j < 3; j++) { Iterator<Long> it = iter.iterator(); Assert.assertEquals(Long.valueOf(-1), it.next()); for (int i = 0; i < 9; i++) { scheduler.advanceTimeBy(1, TimeUnit.SECONDS); Assert.assertEquals(true, it.hasNext()); Assert.assertEquals(Long.valueOf(i), it.next()); } scheduler.advanceTimeBy(1, TimeUnit.SECONDS); Assert.assertEquals(false, it.hasNext()); } }