Class FSM<TState, TData>

Finite state machine (FSM) actor.

Inheritance

object

ActorBase

FSMBase

FSM<TState, TData>

ClusterSingletonManager

Implements

IInternalActor

IListeners

Inherited Members

ActorBase.Sender

ActorBase.Self

ActorBase.Context

ActorBase.AroundReceive(Receive, object)

ActorBase.EmptyReceive

ActorBase.Unhandled(object)

ActorBase.Become(Receive)

ActorBase.BecomeStacked(Receive)

ActorBase.UnbecomeStacked()

ActorBase.SetReceiveTimeout(TimeSpan?)

ActorBase.AroundPreRestart(Exception, object)

ActorBase.AroundPreStart()

ActorBase.PreStart()

ActorBase.AroundPostRestart(Exception, object)

ActorBase.PreRestart(Exception, object)

ActorBase.PostRestart(Exception)

ActorBase.AroundPostStop()

ActorBase.SupervisorStrategy()

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 FSM<TState, TData> : FSMBase, IInternalActor, IListeners

Type Parameters

Name	Description
TState	The state name type
TData	The state data type

Constructors

FSM()

Initializes a new instance of the FSM class.

Declaration

protected FSM()

Fields

DebugEvent

Can be set to enable debugging on certain actions taken by the FSM

Declaration

protected bool DebugEvent

Field Value

Type	Description
bool

Properties

Listeners

Retrieves the support needed to interact with an actor's listeners.

Declaration

public ListenerSupport Listeners { get; }

Property Value

Type	Description
ListenerSupport

NextStateData

Return next state data (available in OnTransition(TransitionHandler) handlers)

Declaration

public TData NextStateData { get; }

Property Value

Type	Description
TData

Exceptions

Type	Condition
InvalidOperationException	This exception is thrown if this property is accessed outside of an OnTransition(TransitionHandler) handler.

StateData

Current state data

Declaration

public TData StateData { get; }

Property Value

Type	Description
TData

Exceptions

Type	Condition
IllegalStateException	This exception is thrown if this property is accessed before StartWith(TState, TData, TimeSpan?) was called.

StateName

Current state name

Declaration

public TState StateName { get; }

Property Value

Type	Description
TState

Exceptions

Type	Condition
IllegalStateException	This exception is thrown if this property is accessed before StartWith(TState, TData, TimeSpan?) was called.

Methods

CancelTimer(string)

Cancel a named FSMBase.Timer, ensuring that the message is not subsequently delivered (no race.)

Declaration

public void CancelTimer(string name)

Parameters

Type	Name	Description
string	name	The name of the timer to cancel.

GoTo(TState)

Produce transition to other state. Return this from a state function in order to effect the transition.

Declaration

public FSMBase.State<TState, TData> GoTo(TState nextStateName)

Parameters

Type	Name	Description
TState	nextStateName	State designator for the next state

Returns

Type	Description
FSMBase.State<TState, TData>	State transition descriptor

GoTo(TState, TData)

Obsolete. Use GoTo(nextStateName).Using(stateData) instead.

Declaration

[Obsolete("This method is obsoleted. Use GoTo(nextStateName).Using(newStateData) [1.2.0]")]
public FSMBase.State<TState, TData> GoTo(TState nextStateName, TData stateData)

Parameters

Type	Name	Description
TState	nextStateName	N/A
TData	stateData	N/A

Returns

Type	Description
FSMBase.State<TState, TData>	N/A

Initialize()

Verify the existence of initial state and setup timers. This should be the last call within the constructor or PreStart() and PostRestart(Exception).

Declaration

public void Initialize()

Exceptions

Type	Condition
IllegalStateException	This exception is thrown when this method is called before StartWith(TState, TData, TimeSpan?) is called.

IsTimerActive(string)

Determines whether the named timer is still active. Returns true unless the timer does not exist, has previously been cancelled, or if it was a single-shot timer whose message was already received.

Declaration

public bool IsTimerActive(string name)

Parameters

Type	Name	Description
string	name	TBD

Returns

Type	Description
bool	TBD

LogTermination(Reason)

By default, Failure is logged at error level and other reason types are not logged. It is possible to override this behavior.

Declaration

protected virtual void LogTermination(FSMBase.Reason reason)

Parameters

Type	Name	Description
FSMBase.Reason	reason	TBD

OnTermination(Action<StopEvent<TState, TData>>)

Set the handler which is called upon termination of this FSM actor. Calling this method again will overwrite the previous contents.

Declaration

public void OnTermination(Action<FSMBase.StopEvent<TState, TData>> terminationHandler)

Parameters

Type	Name	Description
Action<FSMBase.StopEvent<TState, TData>>	terminationHandler	TBD

OnTransition(TransitionHandler)

Set handler which is called upon each state transition

Declaration

public void OnTransition(FSM<TState, TData>.TransitionHandler transitionHandler)

Parameters

Type	Name	Description
FSM<TState, TData>.TransitionHandler	transitionHandler	TBD

PostStop()

Call the OnTermination(Action<StopEvent<TState, TData>>) hook if you want to retain this behavior. When overriding make sure to call base.PostStop();

Please note that this method is called by default from PreRestart(Exception, object) so override that one if OnTermination(Action<StopEvent<TState, TData>>) shall not be called during restart.

Declaration

protected override void PostStop()

Overrides

ActorBase.PostStop()

Receive(object)

Processor for user defined messages.

Declaration

protected override bool Receive(object message)

Parameters

Type	Name	Description
object	message	The message.

Returns

Type	Description
bool	TBD

Overrides

ActorBase.Receive(object)

SetStateTimeout(TState, TimeSpan?)

Set the state timeout explicitly. This method can be safely used from within a state handler.

Declaration

public void SetStateTimeout(TState state, TimeSpan? timeout)

Parameters

Type	Name	Description
TState	state	TBD
TimeSpan?	timeout	TBD

SetTimer(string, object, TimeSpan, bool)

Schedule named timer to deliver message after given delay, possibly repeating. Any existing timer with the same name will automatically be canceled before adding the new timer.

Declaration

public void SetTimer(string name, object msg, TimeSpan timeout, bool repeat = false)

Parameters

Type	Name	Description
string	name	identifier to be used with CancelTimer(string).
object	msg	message to be delivered
TimeSpan	timeout	delay of first message delivery and between subsequent messages.
bool	repeat	send once if false, scheduleAtFixedRate if true

StartWith(TState, TData, TimeSpan?)

Sets the initial state for this FSM. Call this method from the constructor before the Initialize() method. If different state is needed after a restart this method, followed by Initialize(), can be used in the actor life cycle hooks PreStart() and PostRestart(Exception).

Declaration

public void StartWith(TState stateName, TData stateData, TimeSpan? timeout = null)

Parameters

Type	Name	Description
TState	stateName	Initial state designator.
TData	stateData	Initial state data.
TimeSpan?	timeout	State timeout for the initial state, overriding the default timeout for that state.

Stay()

Produce "empty" transition descriptor. Return this from a state function when no state change is to be effected.

Declaration

public FSMBase.State<TState, TData> Stay()

Returns

Type	Description
FSMBase.State<TState, TData>	Descriptor for staying in the current state.

Stop()

Produce change descriptor to stop this FSM actor with FSMBase.Reason FSMBase.Normal

Declaration

public FSMBase.State<TState, TData> Stop()

Returns

Type	Description
FSMBase.State<TState, TData>	Descriptor for stopping in the current state.

Stop(Reason)

Produce change descriptor to stop this FSM actor with the specified FSMBase.Reason.

Declaration

public FSMBase.State<TState, TData> Stop(FSMBase.Reason reason)

Parameters

Type	Name	Description
FSMBase.Reason	reason	Reason why this FSM<TState, TData> is shutting down.

Returns

Type	Description
FSMBase.State<TState, TData>	Descriptor for stopping in the current state.

Stop(Reason, TData)

Produce change descriptor to stop this FSM actor with the specified FSMBase.Reason.

Declaration

public FSMBase.State<TState, TData> Stop(FSMBase.Reason reason, TData stateData)

Parameters

Type	Name	Description
FSMBase.Reason	reason	Reason why this FSM<TState, TData> is shutting down.
TData	stateData	State data.

Returns

Type	Description
FSMBase.State<TState, TData>	Descriptor for stopping in the current state.

Transform(StateFunction)

TBD

Declaration

public FSM<TState, TData>.TransformHelper Transform(FSM<TState, TData>.StateFunction func)

Parameters

Type	Name	Description
FSM<TState, TData>.StateFunction	func	TBD

Returns

Type	Description
FSM<TState, TData>.TransformHelper	TBD

When(TState, StateFunction, TimeSpan?)

Insert a new FSM<TState, TData>.StateFunction at the end of the processing chain for the given state. If the stateTimeout parameter is set, entering this state without a differing explicit timeout setting will trigger a FSMBase.StateTimeout.

Declaration

public void When(TState stateName, FSM<TState, TData>.StateFunction func, TimeSpan? timeout = null)

Parameters

Type	Name	Description
TState	stateName	designator for the state
FSM<TState, TData>.StateFunction	func	delegate describing this state's response to input
TimeSpan?	timeout	default timeout for this state

WhenUnhandled(StateFunction)

Set handler which is called upon reception of unhandled FSM messages. Calling this method again will overwrite the previous contents.

Declaration

public void WhenUnhandled(FSM<TState, TData>.StateFunction stateFunction)

Parameters

Type	Name	Description
FSM<TState, TData>.StateFunction	stateFunction	TBD

Implements

IInternalActor

IListeners

Extension Methods

ObjectExtensions.IsDefaultForType<T>(T)

ObjectExtensions.AsOption<T>(T)

Extensions.AsInstanceOf<T>(object)