stage

Type Members

1.  abstract class AbstractGraphStageWithMaterializedValue[+S <: Shape, M] extends GraphStageWithMaterializedValue[S, M]

   Java API: A GraphStage represents a reusable graph stream processing operator.

   Java API: A GraphStage represents a reusable graph stream processing operator.

   Extend this AbstractGraphStageWithMaterializedValue if you want to provide a materialized value, represented by the type parameter M. If your GraphStage does not need to provide a materialized value you can instead extend which materializes a NotUsed value.

   A GraphStage consists of a which describes its input and output ports and a factory function that creates a GraphStageLogic which implements the processing logic that ties the ports together.

   See also GraphStageWithMaterializedValue for Scala DSL for this operator.

2.  abstract class AbstractInHandler extends InHandler

   Java API: callbacks for an input port where termination logic is predefined (completing when upstream completes, failing when upstream fails).

3.  abstract class AbstractInOutHandler extends with OutHandler

   Java API: callback combination for output and input ports where termination logic is predefined (completing when upstream completes, failing when upstream fails, completing when downstream cancels).

4.  abstract class AbstractOutHandler extends OutHandler

   Java API: callbacks for an output port where termination logic is predefined (completing when downstream cancels).

5.  trait AsyncCallback[T] extends AnyRef

   An asynchronous callback holder that is attached to a GraphStageLogic.

   An asynchronous callback holder that is attached to a . Initializing AsyncCallback#invoke will eventually lead to the registered handler being called.

   This holder has the same lifecycle as a stream and cannot be used before materialization is done.

   Typical use cases are exchanging messages between stream and substreams or invoking from external world sending event to a stream

   Not for user extension

   Annotations

   @DoNotInherit()

6.  abstract class GraphStage[S <: Shape] extends GraphStageWithMaterializedValue[S, NotUsed]

   A GraphStage represents a reusable graph stream processing operator.

   A GraphStage represents a reusable graph stream processing operator.

   A GraphStage consists of a which describes its input and output ports and a factory function that creates a GraphStageLogic which implements the processing logic that ties the ports together.

7.  abstract class GraphStageLogic extends AnyRef

   Represents the processing logic behind a GraphStage.

   Represents the processing logic behind a . Roughly speaking, a subclass of is a collection of the following parts: * A set of and instances and their assignments to the s and s of the enclosing * Possible mutable state, accessible from the and callbacks, but not from anywhere else (as such access would not be thread-safe) * The lifecycle hooks and postStop * Methods for performing stream processing actions, like pulling or pushing elements

   The operator logic is completed once all its input and output ports have been closed. This can be changed by setting setKeepGoing to true.

   The postStop lifecycle hook on the logic itself is called once all ports are closed. This is the only tear down callback that is guaranteed to happen, if the actor system or the materializer is terminated the handlers may never see any callbacks to onUpstreamFailure, onUpstreamFinish or onDownstreamFinish. Therefore operator resource cleanup should always be done in postStop.

8.  abstract class GraphStageLogicWithLogging extends with StageLogging

   Java API: with StageLogging.

9.  abstract class GraphStageWithMaterializedValue[+S <: Shape, +M] extends Graph[S, M]

   Scala API: A GraphStage represents a reusable graph stream processing operator.

   Scala API: A GraphStage represents a reusable graph stream processing operator.

   Extend this GraphStageWithMaterializedValue if you want to provide a materialized value, represented by the type parameter M. If your GraphStage does not need to provide a materialized value you can instead extende which materializes a NotUsed value.

   A GraphStage consists of a which describes its input and output ports and a factory function that creates a GraphStageLogic which implements the processing logic that ties the ports together.

   See also AbstractGraphStageWithMaterializedValue for Java DSL for this operator.

10.  trait InHandler extends AnyRef

    Collection of callbacks for an input port of a GraphStage

11.  trait OutHandler extends AnyRef

    Collection of callbacks for an output port of a GraphStage

12.  trait StageLogging extends AnyRef

    Simple way to obtain a when used together with an akka.stream.Materializer.

    Simple way to obtain a when used together with an . If used with a different materializer akka.event.NoLogging will be returned.

    Make sure to only access log from GraphStage callbacks (such as pull, push or the async-callback).

    Note, abiding to akka.stream.ActorAttributes.logLevels has to be done manually, the logger itself is configured based on the logSource provided to it. Also, the log itself would not know if you're calling it from a "on element" context or not, which is why these decisions have to be handled by the operator itself.

13.  abstract class TimerGraphStageLogic extends GraphStageLogic

    Provides timer related facilities to a GraphStageLogic.

    Provides timer related facilities to a GraphStageLogic.

    To be thread safe the methods of this class must only be called from either the constructor of the graph operator during materialization or one of the methods invoked by the graph operator machinery, such as onPush and onPull.

14.  abstract class TimerGraphStageLogicWithLogging extends with StageLogging

    Java API: with StageLogging.