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Akka.NETAbstractStageTIn, TOut, TPushDirective, TPullDirective, TContext Class

Note: This API is now obsolete.

TBD
Inheritance Hierarchy
SystemObject
  Akka.Streams.StageAbstractStageTIn, TOut
    Akka.Streams.StageAbstractStageTIn, TOut, TPushDirective, TPullDirective, TContext
      Akka.Streams.StageDetachedStageTIn, TOut
      Akka.Streams.StagePushPullStageTIn, TOut

Namespace:  Akka.Streams.Stage
Assembly:  Akka.Streams (in Akka.Streams.dll) Version: 1.2.3.42 (1.2.3.42)
Syntax
[ObsoleteAttribute("Please use GraphStage instead. [1.1.2]")]
public abstract class AbstractStage<TIn, TOut, TPushDirective, TPullDirective, TContext> : AbstractStage<TIn, TOut>
where TPushDirective : IDirective
where TPullDirective : IDirective
where TContext : IContext

Type Parameters

TIn
TBD
TOut
TBD
TPushDirective
TBD
TPullDirective
TBD
TContext
TBD

The AbstractStageTIn, TOut, TPushDirective, TPullDirective, TContext type exposes the following members.

Constructors
  NameDescription
Protected methodAbstractStageTIn, TOut, TPushDirective, TPullDirective, TContext
Initializes a new instance of the AbstractStageTIn, TOut, TPushDirective, TPullDirective, TContext class
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Properties
Methods
  NameDescription
Public methodDecide
If an exception is thrown from OnPush(TIn, IContext) this method is invoked to decide how to handle the exception. By default this method returns Stop.

If an exception is thrown from OnPull(IContext) the stream will always be completed with failure, because it is not always possible to recover from that state. In concrete stages it is of course possible to use ordinary try-catch-recover inside OnPull(IContext) when it is know how to recover from such exceptions.

(Inherited from AbstractStageTIn, TOut.)
Public methodEquals
Determines whether the specified object is equal to the current object.
(Inherited from Object.)
Protected methodFinalize
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.
(Inherited from Object.)
Public methodGetHashCode
Serves as the default hash function.
(Inherited from Object.)
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Protected methodMemberwiseClone
Creates a shallow copy of the current Object.
(Inherited from Object.)
Public methodOnDownstreamFinish(TContext)
This method is called when downstream has cancelled. By default the cancel signal is immediately propagated with Finish.
Public methodOnDownstreamFinish(IContext)
This method is called when downstream has cancelled. By default the cancel signal is immediately propagated with Finish.
(Overrides AbstractStageTIn, TOutOnDownstreamFinish(IContext).)
Public methodOnPull(TContext)
This method is called when there is demand from downstream, i.e. you are allowed to push one element downstreams with Push(Object), or request elements from upstreams with Pull
Public methodOnPull(IContext)
This method is called when there is demand from downstream, i.e. you are allowed to push one element downstreams with Push(Object), or request elements from upstreams with Pull
(Overrides AbstractStageTIn, TOutOnPull(IContext).)
Public methodOnPush(TIn, IContext)

This method is called when an element from upstream is available and there is demand from downstream, i.e. in OnPush(TIn, TContext) you are allowed to call Push(Object) to emit one element downstreams, or you can absorb the element by calling Pull. Note that you can only emit zero or one element downstream from OnPull(TContext).

To emit more than one element you have to push the remaining elements from OnPull(TContext), one-by-one. OnPush(TIn, TContext) is not called again until OnPull(TContext) has requested more elements with Pull.

(Overrides AbstractStageTIn, TOutOnPush(TIn, IContext).)
Public methodOnPush(TIn, TContext)

This method is called when an element from upstream is available and there is demand from downstream, i.e. in OnPush(TIn, TContext) you are allowed to call Push(Object) to emit one element downstreams, or you can absorb the element by calling Pull. Note that you can only emit zero or one element downstream from OnPull(TContext).

To emit more than one element you have to push the remaining elements from OnPull(TContext), one-by-one. OnPush(TIn, TContext) is not called again until OnPull(TContext) has requested more elements with Pull.

Public methodOnUpstreamFailure(Exception, IContext)

OnUpstreamFailure(Exception, IContext) is called when upstream has signaled that the stream is completed with failure. It is not called if OnPull(TContext) or OnPush(TIn, TContext) of the stage itself throws an exception.

Note that elements that were emitted by upstream before the failure happened might not have been received by this stage when OnUpstreamFailure(Exception, IContext) is called, i.e. failures are not backpressured and might be propagated as soon as possible.

Here you cannot call Push(Object), because there might not be any demand from downstream. To emit additional elements before terminating you can use AbsorbTermination and push final elements from OnPull(TContext). The stage will then be in finishing state, which can be checked with IsFinishing.

(Overrides AbstractStageTIn, TOutOnUpstreamFailure(Exception, IContext).)
Public methodOnUpstreamFailure(Exception, TContext)

OnUpstreamFailure(Exception, IContext) is called when upstream has signaled that the stream is completed with failure. It is not called if OnPull(TContext) or OnPush(TIn, TContext) of the stage itself throws an exception.

Note that elements that were emitted by upstream before the failure happened might not have been received by this stage when OnUpstreamFailure(Exception, IContext) is called, i.e. failures are not backpressured and might be propagated as soon as possible.

Here you cannot call Push(Object), because there might not be any demand from downstream. To emit additional elements before terminating you can use AbsorbTermination and push final elements from OnPull(TContext). The stage will then be in finishing state, which can be checked with IsFinishing.

Public methodOnUpstreamFinish(TContext)

This method is called when upstream has signaled that the stream is successfully completed. Here you cannot call Push(Object), because there might not be any demand from downstream. To emit additional elements before terminating you can use AbsorbTermination and push final elements from OnPull(TContext). The stage will then be in finishing state, which can be checked with IsFinishing.

By default the finish signal is immediately propagated with Finish.

IMPORTANT NOTICE: this signal is not back-pressured, it might arrive from upstream even though the last action by this stage was a "push".

Public methodOnUpstreamFinish(IContext)

This method is called when upstream has signaled that the stream is successfully completed. Here you cannot call Push(Object), because there might not be any demand from downstream. To emit additional elements before terminating you can use AbsorbTermination and push final elements from OnPull(TContext). The stage will then be in finishing state, which can be checked with IsFinishing.

By default the finish signal is immediately propagated with Finish.

IMPORTANT NOTICE: this signal is not back-pressured, it might arrive from upstream even though the last action by this stage was a "push".

(Overrides AbstractStageTIn, TOutOnUpstreamFinish(IContext).)
Public methodPostStop
User overridable callback. Is called after the Stages final action is performed. Empty default implementation.
(Inherited from AbstractStageTIn, TOut.)
Public methodPreStart (Inherited from AbstractStageTIn, TOut.)
Public methodRestart
Used to create a fresh instance of the stage after an error resulting in a Restart directive. By default it will return the same instance untouched, so you must override it if there are any state that should be cleared before restarting, e.g. by returning a new instance.
(Inherited from AbstractStageTIn, TOut.)
Public methodToString
Returns a string that represents the current object.
(Inherited from Object.)
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Fields
  NameDescription
Protected fieldContext
TBD
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Extension Methods
See Also