An abstract MaybeObserver that allows asynchronous cancellation by implementing Disposable.

All pre-implemented final methods are thread-safe.

Note that onSuccess(Object), onError(Throwable) and onComplete() are exclusive to each other, unlike a regular Observer, and onComplete() is never called after an onSuccess().

Like all other consumers, DisposableMaybeObserver can be subscribed only once. Any subsequent attempt to subscribe it to a new source will yield an IllegalStateException with message "It is not allowed to subscribe with a(n) <class name> multiple times.".

Implementation of onStart(), onSuccess(Object), onError(Throwable) and onComplete() are not allowed to throw any unchecked exceptions.

Example

Disposable d =
    Maybe.just(1).delay(1, TimeUnit.SECONDS)
    .subscribeWith(new DisposableMaybeObserver<Integer>() {
        @Override public void onStart() {
            System.out.println("Start!");
        }
        @Override public void onSuccess(Integer t) {
            System.out.println(t);
        }
        @Override public void onError(Throwable t) {
            t.printStackTrace();
        }
        @Override public void onComplete() {
            System.out.println("Done!");
        }
    });
// ...
d.dispose();