@Test
public void shouldRedeliverSameResultsToDifferentSubscriber() {
// Use case: When rotating an activity, ObservableManager will re-subscribe original request's
// Observable to a new Observer, which is a member of the new activity instance. In this
// case, we may want to redeliver any previous results (if the request is still being
// managed by ObservableManager).
TestObserver<String> observer = new TestObserver<>();
ReplaySubject<String> subject = ReplaySubject.create();
SubscriptionProxy<String> proxy = SubscriptionProxy.create(subject);
proxy.subscribe(observer);
subject.onNext("Avanti!");
subject.onCompleted();
proxy.unsubscribe();
TestObserver<String> newSubscriber = new TestObserver<>();
proxy.subscribe(newSubscriber);
newSubscriber.awaitTerminalEvent(3, TimeUnit.SECONDS);
newSubscriber.assertCompleted();
newSubscriber.assertValue("Avanti!");
observer.assertCompleted();
observer.assertValue("Avanti!");
}
@Override
public Observable<RibbonResponse<Observable<T>>> observe() {
RibbonHystrixObservableCommand<T> hystrixCommand = request.createHystrixCommand();
ReplaySubject<T> subject = ReplaySubject.create();
hystrixCommand.getObservable().subscribe(subject);
return convertToRibbonResponse(subject, hystrixCommand);
}
@Test
public void shouldKeepDeliveringEventsAfterResubscribed() {
TestObserver<String> observer = new TestObserver<>();
ReplaySubject<String> subject = ReplaySubject.create();
SubscriptionProxy<String> proxy = SubscriptionProxy.create(subject);
proxy.subscribe(observer);
subject.onNext("Avanti 1");
proxy.unsubscribe();
observer = new TestObserver<>();
proxy.subscribe(observer);
subject.onNext("Avanti!");
observer.assertValues("Avanti 1", "Avanti!");
}
@Test
public void shouldCacheResultsWhileUnsubscribedAndDeliverAfterResubscription() {
TestObserver<String> observer = new TestObserver<>();
ReplaySubject<String> subject = ReplaySubject.create();
SubscriptionProxy<String> proxy = SubscriptionProxy.create(subject);
proxy.subscribe(observer);
proxy.unsubscribe();
observer.assertNoValues();
subject.onNext("Avanti!");
subject.onCompleted();
proxy.subscribe(observer);
observer.awaitTerminalEvent(3, TimeUnit.SECONDS);
observer.assertValue("Avanti!");
}
@Test
public void testUnsubscribeBeforeEmit() {
TestObserver<String> observer = new TestObserver<>();
ReplaySubject<String> subject = ReplaySubject.create();
SubscriptionProxy<String> proxy = SubscriptionProxy.create(subject);
proxy.subscribe(observer);
proxy.unsubscribe();
observer.assertNotCompleted();
observer.assertNoValues();
subject.onNext("Avanti!");
subject.onCompleted();
proxy.subscribe(observer);
observer.assertCompleted();
observer.assertValue("Avanti!");
}
@Test
public void testAlreadyUnsubscribedInterleavesWithClient() {
ReplaySubject<Integer> source = ReplaySubject.create();
Subscriber<Integer> done = Subscribers.empty();
done.unsubscribe();
@SuppressWarnings("unchecked")
Observer<Integer> o = mock(Observer.class);
InOrder inOrder = inOrder(o);
Observable<Integer> result = source.publish().refCount();
result.subscribe(o);
source.onNext(1);
result.subscribe(done);
source.onNext(2);
source.onCompleted();
inOrder.verify(o).onNext(1);
inOrder.verify(o).onNext(2);
inOrder.verify(o).onCompleted();
verify(o, never()).onError(any(Throwable.class));
}
/** Created by Administrator on 2016/3/18. */
public class RxBus {
// PublishSubject仅会向Observer释放在订阅之后Observable释放的数据。
private final Subject<Object, Object> publishBus =
new SerializedSubject<>(PublishSubject.create());
// AsyncSubject仅释放Observable释放的最后一个数据，并且仅在Observable完成之后。然而如果当Observable因为异常而终止，AsyncSubject将不会释放任何数据，但是会向Observer传递一个异常通知。
private final Subject<Object, Object> asyncBus = new SerializedSubject<>(AsyncSubject.create());
// 当Observer订阅了一个BehaviorSubject，它一开始就会释放Observable最近释放的一个数据对象，当还没有任何数据释放时，它则是一个默认值。接下来就会释放Observable释放的所有数据。
// 如果Observable因异常终止，BehaviorSubject将不会向后续的Observer释放数据，但是会向Observer传递一个异常通知。
private final Subject<Object, Object> behaviorBus =
new SerializedSubject<>(BehaviorSubject.create());
// 不管Observer何时订阅ReplaySubject，ReplaySubject会向所有Observer释放Observable释放过的数据。
// 有不同类型的ReplaySubject，它们是用来限定Replay的范围，例如设定Buffer的具体大小，或者设定具体的时间范围。
// 如果使用ReplaySubject作为Observer，注意不要在多个线程中调用onNext、onComplete和onError方法，因为这会导致顺序错乱，这个是违反了Observer规则的。
private final Subject<Object, Object> replayBus = new SerializedSubject<>(ReplaySubject.create());
}
/** Responsible for conducting Bluetooth Low Energy peripheral scans. */
@Singleton
public class ScanPresenter extends BasePresenter {
static final String LOG_TAG = ScanPresenter.class.getSimpleName();
/**
* The peripherals found by the scan peripheral. Initially contains an empty list.
*
* <p>This subject will emit an empty list if a peripheral scan fails.
*/
public final ReplaySubject<List<GattPeripheral>> peripherals = ReplaySubject.createWithSize(1);
private final BluetoothStack bluetoothStack;
private final LoggerFacade logger;
private final PeripheralCriteria scanCriteria = new PeripheralCriteria();
private @Nullable Subscription scanSubscription;
@Inject
public ScanPresenter(@NonNull BluetoothStack bluetoothStack, @NonNull LoggerFacade logger) {
this.bluetoothStack = bluetoothStack;
this.logger = logger;
peripherals.onNext(Collections.<GattPeripheral>emptyList());
}
/**
* Starts a Bluetooth Low Energy peripheral scan, if one is not already underway. Results are
* delivered through the {@link #peripherals} subject.
*/
public void scan() {
if (scanSubscription != null) {
return;
}
final Observable<List<GattPeripheral>> scan =
bind(bluetoothStack.discoverPeripherals(scanCriteria));
this.scanSubscription =
scan.subscribe(
new Subscriber<List<GattPeripheral>>() {
@Override
public void onCompleted() {
ScanPresenter.this.scanSubscription = null;
}
@Override
public void onError(Throwable e) {
logger.error(LOG_TAG, "Could not complete scan", e);
peripherals.onNext(Collections.<GattPeripheral>emptyList());
ScanPresenter.this.scanSubscription = null;
}
@Override
public void onNext(List<GattPeripheral> gattPeripherals) {
logger.info(LOG_TAG, "Scan completed with " + gattPeripherals.size() + " results");
peripherals.onNext(gattPeripherals);
}
});
}
// region Attributes
/** Sets the maximum number of peripherals to scan before ending the scan. */
public void setLimit(int limit) {
scanCriteria.setLimit(limit);
}
/** Sets the maximum amount of time that can elapse before a scan is ended. */
public void setDuration(long duration, @NonNull TimeUnit timeUnit) {
scanCriteria.setDuration(timeUnit.toMillis(duration));
}
// endregion
}