Module jakarta.ws.rs

Package jakarta.ws.rs.sse

Interface SseBroadcaster

All Superinterfaces:

AutoCloseable

public interface SseBroadcaster
extends AutoCloseable

Server-Sent events broadcasting facility.

Server broadcaster can be used to manage multiple server sinks. It enables sending events to all registered event outputs and provides facility to effectively handle exceptions and closures of individual registered event outputs.

Instance of this interface is thread safe, meaning that it can be shared and its method invoked from different threads without causing inconsistent internal state.

Since:

2.1

Method Summary

Modifier and Type	Method	Description
CompletionStage<?>	broadcast(OutboundSseEvent event)	Publish an SSE event to all registered SseEventSink instances.
void	close()	Close the broadcaster and all registered SseEventSink instances.
void	close(boolean cascading)	Close the broadcaster and release any resources associated with it.
void	onClose(Consumer<SseEventSink> onClose)	Register a listener, which will be called when this SseBroadcaster closes a given event SseEventSink or tries to write to a given SseEventSink that is already closed (either by client closing the connection or by calling SseEventSink.close() on the server side.
void	onError(BiConsumer<SseEventSink,Throwable> onError)	Register a listener, which will be called when an exception is thrown by a given SseEventSink when this SseBroadcaster tries to write to it or close it.
void	register(SseEventSink sseEventSink)	Register provided SseEventSink instance to this SseBroadcaster.

Method Details

onError

void onError(BiConsumer<SseEventSink,Throwable> onError)

Register a listener, which will be called when an exception is thrown by a given SseEventSink when this SseBroadcaster tries to write to it or close it.

This operation is potentially slow, especially if large number of listeners get registered in the broadcaster. The SseBroadcaster implementation is optimized to efficiently handle small amounts of concurrent listener registrations and removals and large amounts of registered listener notifications.

Parameters:

onError - bi-consumer, taking two parameters: SseEventSink, which is the source of the error and the actual Throwable instance.

onClose

void onClose(Consumer<SseEventSink> onClose)

Register a listener, which will be called when this SseBroadcaster closes a given event SseEventSink or tries to write to a given SseEventSink that is already closed (either by client closing the connection or by calling SseEventSink.close() on the server side.

This operation is potentially slow, especially if large number of listeners get registered in the broadcaster. The SseBroadcaster implementation is optimized to efficiently handle small amounts of concurrent listener registrations and removals and large amounts of registered listener notifications.

Parameters:

onClose - consumer taking single parameter, a SseEventSink, which was closed.

register

void register(SseEventSink sseEventSink)

Register provided SseEventSink instance to this SseBroadcaster.

Parameters:

sseEventSink - to be registered.

broadcast

CompletionStage<?> broadcast(OutboundSseEvent event)

Publish an SSE event to all registered SseEventSink instances.

Parameters:

event - SSE event to be published.

Returns:

completion stage that completes when the event has been broadcast to all registered event sinks.

close

void close()

Close the broadcaster and all registered SseEventSink instances. Any other resources associated with the SseBroadcaster should be released. This method is equivalent to calling close(true).

Subsequent calls have no effect and are ignored. Once the SseBroadcaster is closed, invoking any other method on the broadcaster instance would result in an IllegalStateException being thrown.

Specified by:

close in interface AutoCloseable

close

void close(boolean cascading)

Close the broadcaster and release any resources associated with it. The closing of registered SseEventSink is controlled by the cascading parameter.

Subsequent calls have no effect and are ignored. Once the SseBroadcaster is closed, invoking any other method on the broadcaster instance would result in an IllegalStateException being thrown.

Parameters:

cascading - Boolean value that controls closing of registered SseEventSink instances.