T - the value typepublic abstract classResourceObserver<T>extendsObjectimplementsObserver<T>,Disposable
Observer that allows asynchronous cancellation of its subscription and associated resources.All pre-implemented final methods are thread-safe.
To release the associated resources, one has to calldispose() inonError() andonComplete() explicitly.
Useadd(Disposable) to associate resources (asDisposables) with thisResourceObserver that will be cleaned up whendispose() is called. Removing previously associated resources is not possible but one can create aCompositeDisposable, associate it with thisResourceObserver and then add/remove resources to/from theCompositeDisposable freely.
Use thedispose() to dispose the sequence from within anonNext implementation.
Like all other consumers,ResourceObserver can be subscribed only once. Any subsequent attempt to subscribe it to a new source will yield anIllegalStateException with message"It is not allowed to subscribe with a(n) <class name> multiple times.".
Implementation ofonStart(),Observer.onNext(Object),Observer.onError(Throwable) andObserver.onComplete() are not allowed to throw any unchecked exceptions. If for some reason this can't be avoided, useObservable.safeSubscribe(io.reactivex.Observer) instead of the standardsubscribe() method.
Example
Disposable d = Observable.range(1, 5) .subscribeWith(new ResourceObserver<Integer>() { @Override public void onStart() { add(Schedulers.single() .scheduleDirect(() -> System.out.println("Time!"), 2, TimeUnit.SECONDS)); request(1); } @Override public void onNext(Integer t) { if (t == 3) { dispose(); } System.out.println(t); } @Override public void onError(Throwable t) { t.printStackTrace(); dispose(); } @Override public void onComplete() { System.out.println("Done!"); dispose(); } }); // ... d.dispose();| Constructor and Description |
|---|
ResourceObserver() |
| Modifier and Type | Method and Description |
|---|---|
void | add(Disposable resource)Adds a resource to this ResourceObserver. |
void | dispose()Cancels the main disposable (if any) and disposes the resources associated with this ResourceObserver (if any). |
boolean | isDisposed()Returns true if this ResourceObserver has been disposed/cancelled. |
protected void | onStart()Called once the upstream sets a Subscription on this ResourceObserver. |
void | onSubscribe(Disposable d)Provides the Observer with the means of cancelling (disposing) the connection (channel) with the Observable in both synchronous (from within Observer.onNext(Object)) and asynchronous manner. |
clone,equals,finalize,getClass,hashCode,notify,notifyAll,toString,wait,wait,waitonComplete,onError,onNextpublic final void add(@NonNullDisposable resource)
resource - the resource to addNullPointerException - if resource is nullpublic final void onSubscribe(Disposable d)
ObserverObserver.onNext(Object)) and asynchronous manner.onSubscribe in interface Observer<T>d - the Disposable instance whoseDisposable.dispose() can be called anytime to cancel the connectionprotected void onStart()
You can perform initialization at this moment. The default implementation does nothing.
public final void dispose()
This method can be called before the upstream calls onSubscribe at which case the main Disposable will be immediately disposed.
dispose in interface Disposablepublic final boolean isDisposed()
isDisposed in interface Disposable