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
    Author:
    Marek Potociar
    • Method Detail

      • 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.

        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