RxJava 3 3.1.8 · io.reactivex.rxjava3.core.FlowableEmitter

Abstraction over a Reactive Streams org.reactivestreams.Subscriber that allows associating a resource with it and exposes the current number of downstream requested amount.

The onNext(Object), onError(Throwable), tryOnError(Throwable) and onComplete() methods should be called in a sequential manner, just like the Subscriber's methods. Use the FlowableEmitter the serialize() method returns instead of the original FlowableEmitter instance provided by the generator routine if you want to ensure this. The other methods are thread-safe.

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).

Method Summary

Modifier and Type	Method and Description
public boolean	Returns: true if the downstream cancelled the sequence or the emitter was terminated isCancelled() Returns true if the downstream cancelled the sequence or the emitter was terminated via `onError(Throwable)`, `onComplete` or a successful `tryOnError(Throwable)`.
public long	Returns: the current outstanding request amount requested() The current outstanding request amount.
public @NonNull FlowableEmitter<T>	Returns: the serialized `FlowableEmitter` serialize() Ensures that calls to `onNext`, `onError` and `onComplete` are properly serialized.
public void	setCancellable(@Nullable Cancellable the `Cancellable` resource, `null` is allowed c) Sets a `Cancellable` on this emitter; any previous `Disposable` or `Cancellable` will be disposed/cancelled.
public void	setDisposable(@Nullable Disposable the disposable, `null` is allowed d) Sets a Disposable on this emitter; any previous `Disposable` or `Cancellable` will be disposed/cancelled.
public boolean	Returns: true if successful, false if the downstream is not able to accept further events tryOnError(@NonNull Throwable the throwable error to signal if possible t) Attempts to emit the specified `Throwable` error if the downstream hasn't cancelled the sequence or is otherwise terminated, returning false if the emission is not allowed to happen due to lifecycle restrictions.

Inherited from io.reactivex.rxjava3.core.Emitter:: onComplete onError onNext

Method Detail

isCancelled back to summary

isCancelled	back to summary
public boolean isCancelled() Returns true if the downstream cancelled the sequence or the emitter was terminated via `onError(Throwable)`, `onComplete` or a successful `tryOnError(Throwable)`. This method is thread-safe. Returns:boolean true if the downstream cancelled the sequence or the emitter was terminated

public boolean isCancelled()

Returns true if the downstream cancelled the sequence or the emitter was terminated via onError(Throwable), onComplete or a successful tryOnError(Throwable).

This method is thread-safe.

Returns:boolean: true if the downstream cancelled the sequence or the emitter was terminated

requested	back to summary
public long requested() The current outstanding request amount. This method is thread-safe. Returns:long the current outstanding request amount

requested

back to summary

public long requested()

The current outstanding request amount.

This method is thread-safe.

Returns:long: the current outstanding request amount

serialize back to summary

serialize	back to summary
public @NonNull FlowableEmitter<T> serialize() Ensures that calls to `onNext`, `onError` and `onComplete` are properly serialized. Returns:@NonNull FlowableEmitter<T> the serialized `FlowableEmitter` Annotations @NonNull

public @NonNull FlowableEmitter<T> serialize()

Ensures that calls to onNext, onError and onComplete are properly serialized.

Returns:@NonNull FlowableEmitter<T>

the serialized FlowableEmitter

Annotations

@NonNull

setCancellable back to summary

setCancellable	back to summary
public void setCancellable(@Nullable Cancellable c) Sets a `Cancellable` on this emitter; any previous `Disposable` or `Cancellable` will be disposed/cancelled. This method is thread-safe. Parameters c:@Nullable Cancellable the `Cancellable` resource, `null` is allowed

public void setCancellable(@Nullable Cancellable c)

Sets a Cancellable on this emitter; any previous Disposable or Cancellable will be disposed/cancelled.

This method is thread-safe.

Parameters

c:@Nullable Cancellable: the Cancellable resource, null is allowed

setDisposable back to summary

setDisposable	back to summary
public void setDisposable(@Nullable Disposable d) Sets a Disposable on this emitter; any previous `Disposable` or `Cancellable` will be disposed/cancelled. This method is thread-safe. Parameters d:@Nullable Disposable the disposable, `null` is allowed

public void setDisposable(@Nullable Disposable d)

Sets a Disposable on this emitter; any previous Disposable or Cancellable will be disposed/cancelled.

This method is thread-safe.

Parameters

d:@Nullable Disposable: the disposable, null is allowed

tryOnError back to summary

tryOnError	back to summary
public boolean tryOnError(@NonNull Throwable t) Attempts to emit the specified `Throwable` error if the downstream hasn't cancelled the sequence or is otherwise terminated, returning false if the emission is not allowed to happen due to lifecycle restrictions. Unlike `onError(Throwable)`, the `RxjavaPlugins.onError` is not called if the error could not be delivered. History: 2.1.1 - experimental Parameters t:@NonNull Throwable the throwable error to signal if possible Returns:boolean true if successful, false if the downstream is not able to accept further events Since 2.2

public boolean tryOnError(@NonNull Throwable t)

Attempts to emit the specified Throwable error if the downstream hasn't cancelled the sequence or is otherwise terminated, returning false if the emission is not allowed to happen due to lifecycle restrictions.

Unlike onError(Throwable), the RxjavaPlugins.onError is not called if the error could not be delivered.

History: 2.1.1 - experimental

Parameters

t:@NonNull Throwable: the throwable error to signal if possible

Returns:boolean

true if successful, false if the downstream is not able to accept further events

Since

2.2

public Interface FlowableEmitter<T>

Method Summary

Method Detail