public interface CompletableObserver
When a CompletableObserver
is subscribed to a CompletableSource
through the CompletableSource.subscribe(CompletableObserver)
method,
the CompletableSource
calls onSubscribe(Disposable)
with a Disposable
that allows
disposing the sequence at any time. A well-behaved
CompletableSource
will call a CompletableObserver
's onError(Throwable)
or onComplete()
method exactly once as they are considered mutually exclusive terminal signals.
Calling the CompletableObserver
's method must happen in a serialized fashion, that is, they must not
be invoked concurrently by multiple threads in an overlapping fashion and the invocation pattern must
adhere to the following protocol:
onSubscribe (onError | onComplete)?
Subscribing a CompletableObserver
to multiple CompletableSource
s is not recommended. If such reuse
happens, it is the duty of the CompletableObserver
implementation to be ready to receive multiple calls to
its methods and ensure proper concurrent behavior of its business logic.
Calling onSubscribe(Disposable)
or onError(Throwable)
with a
null
argument is forbidden.
The implementations of the onXXX
methods should avoid throwing runtime exceptions other than the following cases:
null
, the methods can throw a NullPointerException
.
Note though that RxJava prevents null
s to enter into the flow and thus there is generally no
need to check for nulls in flows assembled from standard sources and intermediate operators.
VirtualMachineError
).Modifier and Type | Method and Description |
---|---|
void |
onComplete()
Called once the deferred computation completes normally.
|
void |
onError(Throwable e)
Called once if the deferred computation 'throws' an exception.
|
void |
onSubscribe(Disposable d)
Called once by the Completable to set a Disposable on this instance which
then can be used to cancel the subscription at any time.
|
void onSubscribe(@NonNull Disposable d)
d
- the Disposable instance to call dispose on for cancellation, not nullvoid onComplete()