public Interface CompletableEmitter

All methods are safe to call from multiple threads, but note that there is no guarantee whose terminal event will win and get delivered to the downstream.

Calling onComplete() multiple times has no effect. Calling onError(Throwable) multiple times or after onComplete will route the exception into the global error handler via io.reactivex.rxjava3.plugins.RxJavaPlugins#onError(Throwable).

The emitter allows the registration of a single resource, in the form of a Disposable or Cancellable via setDisposable(Disposable) or setCancellable(Cancellable) respectively. The emitter implementations will dispose/cancel this instance when the downstream cancels the flow or after the event generator logic calls onError(Throwable), onComplete() or when tryOnError(Throwable) succeeds.

Only one Disposable or Cancellable object can be associated with the emitter at a time. Calling either set method will dispose/cancel any previous object. If there is a need for handling multiple resources, one can create a io.reactivex.rxjava3.disposables.CompositeDisposable and associate that with the emitter instead.

The Cancellable is logically equivalent to Disposable but allows using cleanup logic that can throw a checked exception (such as many close() methods on Java IO components). Since the release of resources happens after the terminal events have been delivered or the sequence gets cancelled, exceptions throw within Cancellable are routed to the global error handler via io.reactivex.rxjava3.plugins.RxJavaPlugins#onError(Throwable).