Class ActorSource


  • public class ActorSource
    extends java.lang.Object
    Collection of Sources aimed at integrating with typed Actors.
    • Constructor Detail

      • ActorSource

        public ActorSource()
    • Method Detail

      • actorRef

        public static <T> Source<T,​ActorRef<T>> actorRef​(java.util.function.Predicate<T> completionMatcher,
                                                               Function<T,​java.util.Optional<java.lang.Throwable>> failureMatcher,
                                                               int bufferSize,
                                                               OverflowStrategy overflowStrategy)
        Creates a Source that is materialized as an ActorRef. Messages sent to this actor will be emitted to the stream if there is demand from downstream, otherwise they will be buffered until request for demand is received.

        Depending on the defined OverflowStrategy it might drop elements if there is no space available in the buffer.

        The strategy akka.stream.OverflowStrategy.backpressure is not supported, and an IllegalArgument("Backpressure overflowStrategy not supported") will be thrown if it is passed as argument.

        The buffer can be disabled by using bufferSize of 0 and then received messages are dropped if there is no demand from downstream. When bufferSize is 0 the overflowStrategy does not matter. An async boundary is added after this Source; as such, it is never safe to assume the downstream will always generate demand.

        The stream can be completed successfully by sending the actor reference a Status.Success (whose content will be ignored) in which case already buffered elements will be signaled before signaling completion, or by sending PoisonPill in which case completion will be signaled immediately.

        The stream can be completed with failure by sending a Status.Failure to the actor reference. In case the Actor is still draining its internal buffer (after having received a Status.Success) before signaling completion and it receives a Status.Failure, the failure will be signaled downstream immediately (instead of the completion signal).

        The actor will be stopped when the stream is completed, failed or canceled from downstream, i.e. you can watch it to get notified when that happens.

        See also akka.stream.javadsl.Source.queue.

        Parameters:
        bufferSize - The size of the buffer in element count
        overflowStrategy - Strategy that is used when incoming elements cannot fit inside the buffer
      • actorRefWithBackpressure

        public static <T,​Ack> Source<T,​ActorRef<T>> actorRefWithBackpressure​(ActorRef<Ack> ackTo,
                                                                                         Ack ackMessage,
                                                                                         Function<T,​java.util.Optional<CompletionStrategy>> completionMatcher,
                                                                                         Function<T,​java.util.Optional<java.lang.Throwable>> failureMatcher)
        Creates a Source that is materialized as an ActorRef. Messages sent to this actor will be emitted to the stream if there is demand from downstream, and a new message will only be accepted after the previous messages has been consumed and acknowledged back. The stream will complete with failure if a message is sent before the acknowledgement has been replied back.

        The stream can be completed by sending a message that is matched by completionMatcher which decides if the stream is to drained before completion or should complete immediately.

        A message that is matched by failureMatcher fails the stream. The extracted Throwable will be used to fail the stream. In case the Actor is still draining its internal buffer (after having received a message matched by completionMatcher) before signaling completion and it receives a message matched by failureMatcher, the failure will be signaled downstream immediately (instead of the completion signal).

        The actor will be stopped when the stream is completed, failed or canceled from downstream, i.e. you can watch it to get notified when that happens.

      • actorRefWithAck

        public static <T,​Ack> Source<T,​ActorRef<T>> actorRefWithAck​(ActorRef<Ack> ackTo,
                                                                                Ack ackMessage,
                                                                                Function<T,​java.util.Optional<CompletionStrategy>> completionMatcher,
                                                                                Function<T,​java.util.Optional<java.lang.Throwable>> failureMatcher)
        Deprecated.
        Use actorRefWithBackpressure instead
        Creates a Source that is materialized as an ActorRef. Messages sent to this actor will be emitted to the stream if there is demand from downstream, and a new message will only be accepted after the previous messages has been consumed and acknowledged back. The stream will complete with failure if a message is sent before the acknowledgement has been replied back.

        The stream can be completed with failure by sending a message that is matched by failureMatcher. The extracted Throwable will be used to fail the stream. In case the Actor is still draining its internal buffer (after having received a message matched by completionMatcher) before signaling completion and it receives a message matched by failureMatcher, the failure will be signaled downstream immediately (instead of the completion signal).

        The actor will be stopped when the stream is completed, failed or canceled from downstream, i.e. you can watch it to get notified when that happens.