c

akka.projection.javadsl

StatefulHandler

abstract class StatefulHandler[State, Envelope] extends Handler[Envelope]

Source
StatefulHandler.scala
Linear Supertypes
Handler[Envelope], HandlerLifecycle, AnyRef, Any
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Inherited
  1. StatefulHandler
  2. Handler
  3. HandlerLifecycle
  4. AnyRef
  5. Any
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Visibility
  1. Public
  2. Protected

Instance Constructors

  1. new StatefulHandler()

Abstract Value Members

  1. abstract def initialState(): CompletionStage[State]

    Invoked to load the initial state when the projection is started or if previous process failed.

  2. abstract def process(state: State, envelope: Envelope): CompletionStage[State]

    The process method is invoked for each Envelope.

    The process method is invoked for each Envelope. One envelope is processed at a time. The returned CompletionStage<State> is to be completed when the processing of the envelope has finished. It will not be invoked with the next envelope until after the returned CompletionStage has been completed.

    The state is the completed value of the previously returned CompletionStage<State> or the initialState. If the previously returned CompletionStage<State> failed it will call initialState again and use that value.

    Annotations
    @throws(classOf[Exception])

Concrete Value Members

  1. final def process(envelope: Envelope): CompletionStage[Done]

    Calls process(state, envelope) with the completed value of the previously returned CompletionStage<State> or the initialState.

    Calls process(state, envelope) with the completed value of the previously returned CompletionStage<State> or the initialState. If the previously returned CompletionStage<State> failed it will call initialState again and use that value.

    Definition Classes
    StatefulHandler → Handler
  2. final def start(): CompletionStage[Done]

    Calls StatefulHandler.initialState when the projection is started.

    Calls StatefulHandler.initialState when the projection is started.

    Definition Classes
    StatefulHandler → Handler → HandlerLifecycle
  3. def stop(): CompletionStage[Done]

    Invoked when the projection has been stopped.

    Invoked when the projection has been stopped. Can be overridden to implement resource cleanup. It is also called when the Projection is restarted after a failure.

    Definition Classes
    Handler → HandlerLifecycle