Class SupervisorStrategy

Base class for supervision strategies

Inheritance

object

SupervisorStrategy

AllForOneStrategy

OneForOneStrategy

DelegatingSupervisorStrategy

Implements

ISurrogated

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: Akka.Actor

Assembly: Akka.dll

Syntax

public abstract class SupervisorStrategy : ISurrogated

Fields

DefaultDecider

When supervisorStrategy is not specified for an actor this Decider is used by default in the supervisor strategy. The child will be stopped when ActorInitializationException, ActorKilledException, or DeathPactException is thrown. It will be restarted for other Exception types. The error is escalated if it's a Exception, i.e. Error.

Declaration

public static IDecider DefaultDecider

Field Value

Type	Description
IDecider	Directive.

DefaultStrategy

When supervisorStrategy is not specified for an actor this is used by default. OneForOneStrategy with decider defined in DefaultDecider.

Declaration

public static readonly SupervisorStrategy DefaultStrategy

Field Value

Type	Description
SupervisorStrategy

StoppingStrategy

This strategy resembles Erlang in that failing children are always terminated (one-for-one).

Declaration

public static readonly OneForOneStrategy StoppingStrategy

Field Value

Type	Description
OneForOneStrategy

Properties

Decider

TBD

Declaration

public abstract IDecider Decider { get; }

Property Value

Type	Description
IDecider

LoggingEnabled

Determines if failures are logged

Declaration

protected bool LoggingEnabled { get; set; }

Property Value

Type	Description
bool

Methods

Handle(IActorRef, Exception)

Determines which Directive this strategy uses to handle exception that occur in the child actor.

Declaration

protected abstract Directive Handle(IActorRef child, Exception exception)

Parameters

Type	Name	Description
IActorRef	child	The child actor where the exception occurred.
Exception	exception	The exception that was thrown.

Returns

Type	Description
Directive	The directive used to handle the exception.

HandleChildTerminated(IActorContext, IActorRef, IEnumerable<IInternalActorRef>)

This method is called after the child has been removed from the set of children. It does not need to do anything special. Exceptions thrown from this method do NOT make the actor fail if this happens during termination.

Declaration

public abstract void HandleChildTerminated(IActorContext actorContext, IActorRef child, IEnumerable<IInternalActorRef> children)

Parameters

Type	Name	Description
IActorContext	actorContext	TBD
IActorRef	child	TBD
IEnumerable<IInternalActorRef>	children	TBD

HandleFailure(ActorCell, IActorRef, Exception, ChildRestartStats, IReadOnlyCollection<ChildRestartStats>)

This is the main entry point: in case of a child’s failure, this method must try to handle the failure by resuming, restarting or stopping the child (and returning true), or it returns false to escalate the failure, which will lead to this actor re-throwing the exception which caused the failure. The exception will not be wrapped. This method calls SupervisorStrategy, which will log the failure unless it is escalated. You can customize the logging by setting SupervisorStrategy to false and do the logging inside the decider or override the LogFailure method.

Declaration

public bool HandleFailure(ActorCell actorCell, IActorRef child, Exception cause, ChildRestartStats stats, IReadOnlyCollection<ChildRestartStats> children)

Parameters

Type	Name	Description
ActorCell	actorCell	The actor cell.
IActorRef	child	The child actor.
Exception	cause	The cause.
ChildRestartStats	stats	The stats for the failed child.
IReadOnlyCollection<ChildRestartStats>	children	TBD

Returns

Type	Description
bool	true if the child actor was handled, otherwise false.

LogFailure(IActorContext, IActorRef, Exception, Directive)

Logs the failure.

Declaration

protected virtual void LogFailure(IActorContext context, IActorRef child, Exception cause, Directive directive)

Parameters

Type	Name	Description
IActorContext	context	The actor cell.
IActorRef	child	The child.
Exception	cause	The cause.
Directive	directive	The directive.

ProcessFailure(IActorContext, bool, IActorRef, Exception, ChildRestartStats, IReadOnlyCollection<ChildRestartStats>)

This method is called to act on the failure of a child: restart if the flag is true, stop otherwise.

Declaration

public abstract void ProcessFailure(IActorContext context, bool restart, IActorRef child, Exception cause, ChildRestartStats stats, IReadOnlyCollection<ChildRestartStats> children)

Parameters

Type	Name	Description
IActorContext	context	The actor context.
bool	restart	if set to true restart, stop otherwise.
IActorRef	child	The child actor
Exception	cause	The exception that caused the child to fail.
ChildRestartStats	stats	The stats for the child that failed. The ActorRef to the child can be obtained via the Child property
IReadOnlyCollection<ChildRestartStats>	children	The stats for all children

RestartChild(IActorRef, Exception, bool)

Restarts the child.

Declaration

protected void RestartChild(IActorRef child, Exception cause, bool suspendFirst)

Parameters

Type	Name	Description
IActorRef	child	The child.
Exception	cause	The cause.
bool	suspendFirst	if set to true [suspend first].

ResumeChild(IActorRef, Exception)

Resumes the previously failed child. Suspend/resume needs to be done in matching pairs, otherwise actors will wake up too soon or never at all.

note

Never apply this to a child which is not the currently failing child.

Declaration

protected void ResumeChild(IActorRef child, Exception exception)

Parameters

Type	Name	Description
IActorRef	child	The child actor that is being resumed.
Exception	exception	The exception that caused the child actor to fail.

ToSurrogate(ActorSystem)

Creates a surrogate representation of the current SupervisorStrategy.

Declaration

public abstract ISurrogate ToSurrogate(ActorSystem system)

Parameters

Type	Name	Description
ActorSystem	system	The actor system that owns this router.

Returns

Type	Description
ISurrogate	The surrogate representation of the current SupervisorStrategy.

Implements

ISurrogated

Extension Methods

ObjectExtensions.IsDefaultForType<T>(T)

ObjectExtensions.AsOption<T>(T)

Extensions.AsInstanceOf<T>(object)