All Superinterfaces:

Actor, ActorLogging, Listeners

All Known Subinterfaces:

LoggingFSM<S,D>

All Known Implementing Classes:

AbstractFSM, AbstractFSMWithStash, AbstractLoggingFSM, BarrierCoordinator, ClientFSM, ClusterSingletonManager, ProtocolStateActor, ServerFSM, ThrottledAssociation
```
public interface FSM<S,D>
extends Actor, Listeners, ActorLogging
```
This extractor is just convenience for matching a (S, S) pair, including a reminder what the new state is.

Nested Class Summary

Nested Classes
Modifier and Type	Interface	Description
`static class`	`FSM.$minus$greater$`
`static class`	`FSM.CurrentState<S>`
`static class`	`FSM.CurrentState$`
`static class`	`FSM.Event<D>`
`static class`	`FSM.Event$`
`static class`	`FSM.Failure`
`static class`	`FSM.Failure$`
`static class`	`FSM.FixedDelayMode$`
`static class`	`FSM.FixedRateMode$`
`static class`	`FSM.LogEntry<S,D>`	Log Entry of the `LoggingFSM`, can be obtained by calling `getLog`.
`static class`	`FSM.LogEntry$`
`static class`	`FSM.Normal$`
`static class`	`FSM.NullFunction$`
`static interface`	`FSM.Reason`
`static class`	`FSM.Shutdown$`
`static class`	`FSM.SilentState<S,D>`	INTERNAL API
`static class`	`FSM.SingleMode$`
`static class`	`FSM.State<S,D>`
`static class`	`FSM.State$`
`static class`	`FSM.StateTimeout$`
`static class`	`FSM.StopEvent<S,D>`
`static class`	`FSM.StopEvent$`
`static class`	`FSM.SubscribeTransitionCallBack`
`static class`	`FSM.SubscribeTransitionCallBack$`
`static class`	`FSM.Timer`
`static class`	`FSM.Timer$`
`static interface`	`FSM.TimerMode`
`static class`	`FSM.TransformHelper`
`static class`	`FSM.Transition<S>`
`static class`	`FSM.Transition$`
`static class`	`FSM.UnsubscribeTransitionCallBack`
`static class`	`FSM.UnsubscribeTransitionCallBack$`

Nested classes/interfaces inherited from interface akka.actor.Actor
Actor.emptyBehavior$, Actor.ignoringBehavior$

Method Summary

All Methods Instance Methods Abstract Methods Deprecated Methods
Modifier and Type	Method	Description
`FSM.$minus$greater$`	`$minus$greater()`	This extractor is just convenience for matching a (S, S) pair, including a reminder what the new state is.
`void`	`akka$actor$FSM$_setter_$Event_$eq(FSM.Event$ x$1)`
`void`	`akka$actor$FSM$_setter_$StateTimeout_$eq(FSM.StateTimeout$ x$1)`	This case object is received in case of a state timeout.
`void`	`akka$actor$FSM$_setter_$StopEvent_$eq(FSM.StopEvent$ x$1)`
`void`	`applyState(FSM.State<S,D> nextState)`
`void`	`cancelTimer(java.lang.String name)`	Cancel named timer, ensuring that the message is not subsequently delivered (no race).
`void`	`currentState_$eq(FSM.State<S,D> x$1)`
`boolean`	`debugEvent()`
`FSM.Event$`	`Event()`
`void`	`generation_$eq(long x$1)`
`void`	`handleEvent_$eq(scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> x$1)`
`void`	`handleTransition(S prev, S next)`
`void`	`initialize()`	Verify existence of initial state and setup timers.
`boolean`	`isStateTimerActive()`	INTERNAL API, used for testing.
`boolean`	`isTimerActive(java.lang.String name)`	Inquire whether the named timer is still active.
`void`	`logTermination(FSM.Reason reason)`	By default `FSM.Failure` is logged at error level and other reason types are not logged.
`void`	`makeTransition(FSM.State<S,D> nextState)`
`void`	`nextState_$eq(FSM.State<S,D> x$1)`
`D`	`nextStateData()`	Return next state data (available in onTransition handlers)
`void`	`onTermination(scala.PartialFunction<FSM.StopEvent<S,D>,scala.runtime.BoxedUnit> terminationHandler)`	Set handler which is called upon termination of this FSM actor.
`void`	`onTransition(scala.PartialFunction<scala.Tuple2<S,S>,scala.runtime.BoxedUnit> transitionHandler)`	Set handler which is called upon each state transition, i.e.
`void`	`postStop()`	Call `onTermination` hook; if you want to retain this behavior when overriding make sure to call `super.postStop()`.
`void`	`processEvent(FSM.Event<D> event, java.lang.Object source)`
`void`	`processMsg(java.lang.Object value, java.lang.Object source)`
`scala.PartialFunction<java.lang.Object,scala.runtime.BoxedUnit>`	`receive()`	Scala API: This defines the initial actor behavior, it must return a partial function with the actor logic.
`void`	`register(S name, scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> function, scala.Option<scala.concurrent.duration.FiniteDuration> timeout)`
`void`	`setStateTimeout(S state, scala.Option<scala.concurrent.duration.FiniteDuration> timeout)`	Set state timeout explicitly.
`void`	`setTimer(java.lang.String name, java.lang.Object msg, scala.concurrent.duration.FiniteDuration timeout, boolean repeat)`	Deprecated. Use startSingleTimer, startTimerWithFixedDelay or startTimerAtFixedRate instead.
`boolean`	`setTimer$default$4()`
`void`	`startSingleTimer(java.lang.String name, java.lang.Object msg, scala.concurrent.duration.FiniteDuration delay)`	Start a timer that will send `msg` once to the `self` actor after the given `delay`.
`void`	`startTimer(java.lang.String name, java.lang.Object msg, scala.concurrent.duration.FiniteDuration timeout, FSM.TimerMode mode)`
`void`	`startTimerAtFixedRate(java.lang.String name, java.lang.Object msg, scala.concurrent.duration.FiniteDuration interval)`	Schedules a message to be sent repeatedly to the `self` actor with a given frequency.
`void`	`startTimerWithFixedDelay(java.lang.String name, java.lang.Object msg, scala.concurrent.duration.FiniteDuration delay)`	Schedules a message to be sent repeatedly to the `self` actor with a fixed `delay` between messages.
`void`	`startWith(S stateName, D stateData, scala.Option<scala.concurrent.duration.FiniteDuration> timeout)`	Set initial state.
`scala.Option<scala.concurrent.duration.FiniteDuration>`	`startWith$default$3()`
`D`	`stateData()`	Return current state data (i.e.
`S`	`stateName()`	Return current state name (i.e.
`FSM.StateTimeout$`	`StateTimeout()`	This case object is received in case of a state timeout.
`FSM.State<S,D>`	`stay()`	Produce "empty" transition descriptor.
`FSM.State<S,D>`	`stop()`	Produce change descriptor to stop this FSM actor with reason "Normal".
`FSM.State<S,D>`	`stop(FSM.Reason reason)`	Produce change descriptor to stop this FSM actor including specified reason.
`FSM.State<S,D>`	`stop(FSM.Reason reason, D stateData)`	Produce change descriptor to stop this FSM actor including specified reason.
`FSM.StopEvent$`	`StopEvent()`
`void`	`super$postStop()`	Call `onTermination` hook; if you want to retain this behavior when overriding make sure to call `super.postStop()`.
`void`	`terminate(FSM.State<S,D> nextState)`
`void`	`terminateEvent_$eq(scala.PartialFunction<FSM.StopEvent<S,D>,scala.runtime.BoxedUnit> x$1)`
`void`	`timeoutFuture_$eq(scala.Option<Cancellable> x$1)`
`scala.PartialFunction<scala.Tuple2<S,S>,scala.runtime.BoxedUnit>`	`total2pf(scala.Function2<S,S,scala.runtime.BoxedUnit> transitionHandler)`	Convenience wrapper for using a total function instead of a partial function literal.
`FSM.TransformHelper`	`transform(scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> func)`
`void`	`transitionEvent_$eq(scala.collection.immutable.List<scala.PartialFunction<scala.Tuple2<S,S>,scala.runtime.BoxedUnit>> x$1)`
`void`	`when(S stateName, scala.concurrent.duration.FiniteDuration stateTimeout, scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> stateFunction)`	Insert a new StateFunction at the end of the processing chain for the given state.
`scala.concurrent.duration.FiniteDuration`	`when$default$2()`
`void`	`whenUnhandled(scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> stateFunction)`	Set handler which is called upon reception of unhandled messages.

Methods inherited from interface akka.actor.Actor
akka$actor$Actor$_setter_$context_$eq, akka$actor$Actor$_setter_$self_$eq, aroundPostRestart, aroundPostStop, aroundPreRestart, aroundPreStart, aroundReceive, context, postRestart, preRestart, preStart, self, sender, supervisorStrategy, unhandled

Methods inherited from interface akka.actor.ActorLogging
_log_$eq, log

Methods inherited from interface akka.routing.Listeners
akka$routing$Listeners$_setter_$listeners_$eq, gossip, gossip$default$2, listenerManagement, listeners

- Method Detail
  - akka$actor$FSM$_setter_$Event_$eq
```
void akka$actor$FSM$_setter_$Event_$eq(FSM.Event$ x$1)
```
  - akka$actor$FSM$_setter_$StopEvent_$eq
```
void akka$actor$FSM$_setter_$StopEvent_$eq(FSM.StopEvent$ x$1)
```
  - akka$actor$FSM$_setter_$StateTimeout_$eq
```
void akka$actor$FSM$_setter_$StateTimeout_$eq(FSM.StateTimeout$ x$1)
```
    This case object is received in case of a state timeout.
    
    Parameters:
    
    x$1 - (undocumented)
  - super$postStop
```
void super$postStop()
```
    Call onTermination hook; if you want to retain this behavior when overriding make sure to call super.postStop().
    Please note that this method is called by default from preRestart(), so override that one if onTermination shall not be called during restart.
  - Event
```
FSM.Event$ Event()
```
  - StopEvent
```
FSM.StopEvent$ StopEvent()
```
  - $minus$greater
```
FSM.$minus$greater$ $minus$greater()
```
    This extractor is just convenience for matching a (S, S) pair, including a reminder what the new state is.
    
    Returns:
    
    (undocumented)
  - StateTimeout
```
FSM.StateTimeout$ StateTimeout()
```
    This case object is received in case of a state timeout.
    
    Returns:
    
    (undocumented)
  - when
```
void when(S stateName,
          scala.concurrent.duration.FiniteDuration stateTimeout,
          scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> stateFunction)
```
    Insert a new 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 StateTimeout event; the same is true when using #stay.
    
    Parameters:
    
    stateName - designator for the state
    
    stateTimeout - default state timeout for this state
    
    stateFunction - partial function describing response to input
  - when$default$2
```
scala.concurrent.duration.FiniteDuration when$default$2()
```
  - startWith
```
void startWith(S stateName,
               D stateData,
               scala.Option<scala.concurrent.duration.FiniteDuration> timeout)
```
    Set initial state. 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 Actor.preStart() and Actor.postRestart(java.lang.Throwable).
    
    Parameters:
    
    stateName - initial state designator
    
    stateData - initial state data
    
    timeout - state timeout for the initial state, overriding the default timeout for that state
  - startWith$default$3
```
scala.Option<scala.concurrent.duration.FiniteDuration> startWith$default$3()
```
  - stay
```
FSM.State<S,D> stay()
```
    Produce "empty" transition descriptor. Return this from a state function when no state change is to be effected.
    No transition event will be triggered by stay(). If you want to trigger an event like S -> S for onTransition to handle use goto instead.
    
    Returns:
    
    descriptor for staying in current state
  - stop
```
FSM.State<S,D> stop()
```
    Produce change descriptor to stop this FSM actor with reason "Normal".
    
    Returns:
    
    (undocumented)
  - stop
```
FSM.State<S,D> stop(FSM.Reason reason)
```
    Produce change descriptor to stop this FSM actor including specified reason.
    
    Parameters:
    
    reason - (undocumented)
    
    Returns:
    
    (undocumented)
  - stop
```
FSM.State<S,D> stop(FSM.Reason reason,
                          D stateData)
```
    Produce change descriptor to stop this FSM actor including specified reason.
    
    Parameters:
    
    reason - (undocumented)
    
    stateData - (undocumented)
    
    Returns:
    
    (undocumented)
  - transform
```
FSM.TransformHelper transform(scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> func)
```
  - startTimerWithFixedDelay
```
void startTimerWithFixedDelay(java.lang.String name,
                              java.lang.Object msg,
                              scala.concurrent.duration.FiniteDuration delay)
```
    Schedules a message to be sent repeatedly to the self actor with a fixed delay between messages.
    It will not compensate the delay between messages if scheduling is delayed longer than specified for some reason. The delay between sending of subsequent messages will always be (at least) the given delay.
    In the long run, the frequency of messages will generally be slightly lower than the reciprocal of the specified delay.
    Each timer has a name and if a new timer with same name is started the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started.
    
    Parameters:
    
    name - (undocumented)
    
    msg - (undocumented)
    
    delay - (undocumented)
  - startTimerAtFixedRate
```
void startTimerAtFixedRate(java.lang.String name,
                           java.lang.Object msg,
                           scala.concurrent.duration.FiniteDuration interval)
```
    Schedules a message to be sent repeatedly to the self actor with a given frequency.
    It will compensate the delay for a subsequent message if the sending of previous message was delayed more than specified. In such cases, the actual message interval will differ from the interval passed to the method.
    If the execution is delayed longer than the interval, the subsequent message will be sent immediately after the prior one. This also has the consequence that after long garbage collection pauses or other reasons when the JVM was suspended all "missed" messages will be sent when the process wakes up again.
    In the long run, the frequency of messages will be exactly the reciprocal of the specified interval.
    Warning: startTimerAtFixedRate can result in bursts of scheduled messages after long garbage collection pauses, which may in worst case cause undesired load on the system. Therefore startTimerWithFixedDelay is often preferred.
    Each timer has a name and if a new timer with same name is started the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started.
    
    Parameters:
    
    name - (undocumented)
    
    msg - (undocumented)
    
    interval - (undocumented)
  - startSingleTimer
```
void startSingleTimer(java.lang.String name,
                      java.lang.Object msg,
                      scala.concurrent.duration.FiniteDuration delay)
```
    Start a timer that will send msg once to the self actor after the given delay.
    Each timer has a name and if a new timer with same name is started the previous is cancelled. It is guaranteed that a message from the previous timer is not received, even if it was already enqueued in the mailbox when the new timer was started.
    
    Parameters:
    
    name - (undocumented)
    
    msg - (undocumented)
    
    delay - (undocumented)
  - setTimer
```
void setTimer(java.lang.String name,
              java.lang.Object msg,
              scala.concurrent.duration.FiniteDuration timeout,
              boolean repeat)
```
    Deprecated.
    Use startSingleTimer, startTimerWithFixedDelay or startTimerAtFixedRate instead. This has the same semantics as startTimerAtFixedRate, but startTimerWithFixedDelay is often preferred. Since 2.6.0.
    
    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.
    
    Parameters:
    
    name - identifier to be used with cancelTimer()
    
    msg - message to be delivered
    
    timeout - delay of first message delivery and between subsequent messages
    
    repeat - send once if false, scheduleAtFixedRate if true
  - setTimer$default$4
```
boolean setTimer$default$4()
```
  - startTimer
```
void startTimer(java.lang.String name,
                java.lang.Object msg,
                scala.concurrent.duration.FiniteDuration timeout,
                FSM.TimerMode mode)
```
  - cancelTimer
```
void cancelTimer(java.lang.String name)
```
    Cancel named timer, ensuring that the message is not subsequently delivered (no race).
    
    Parameters:
    
    name - of the timer to cancel
  - isTimerActive
```
boolean isTimerActive(java.lang.String name)
```
    Inquire whether the named timer is still active. Returns true unless the timer does not exist, has previously been canceled or if it was a single-shot timer whose message was already received.
    
    Parameters:
    
    name - (undocumented)
    
    Returns:
    
    (undocumented)
  - setStateTimeout
```
void setStateTimeout(S state,
                     scala.Option<scala.concurrent.duration.FiniteDuration> timeout)
```
    Set state timeout explicitly. This method can safely be used from within a state handler.
    
    Parameters:
    
    state - (undocumented)
    
    timeout - (undocumented)
  - isStateTimerActive
```
boolean isStateTimerActive()
```
    INTERNAL API, used for testing.
    
    Returns:
    
    (undocumented)
  - onTransition
```
void onTransition(scala.PartialFunction<scala.Tuple2<S,S>,scala.runtime.BoxedUnit> transitionHandler)
```
    Set handler which is called upon each state transition, i.e. not when staying in the same state. This may use the pair extractor defined in the FSM companion object like so:
    
    onTransition { case Old -> New => doSomething }
    
    It is also possible to supply a 2-ary function object:
    
    onTransition(handler _) private def handler(from: S, to: S) { ... }
    
    The underscore is unfortunately necessary to enable the nicer syntax shown above (it uses the implicit conversion total2pf under the hood).
    Multiple handlers may be installed, and every one of them will be called, not only the first one matching.
    Parameters:
    
    transitionHandler - (undocumented)
  - total2pf
```
scala.PartialFunction<scala.Tuple2<S,S>,scala.runtime.BoxedUnit> total2pf(scala.Function2<S,S,scala.runtime.BoxedUnit> transitionHandler)
```
    Convenience wrapper for using a total function instead of a partial function literal. To be used with onTransition.
    
    Parameters:
    
    transitionHandler - (undocumented)
    
    Returns:
    
    (undocumented)
  - onTermination
```
void onTermination(scala.PartialFunction<FSM.StopEvent<S,D>,scala.runtime.BoxedUnit> terminationHandler)
```
    Set handler which is called upon termination of this FSM actor. Calling this method again will overwrite the previous contents.
    
    Parameters:
    
    terminationHandler - (undocumented)
  - whenUnhandled
```
void whenUnhandled(scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> stateFunction)
```
    Set handler which is called upon reception of unhandled messages. Calling this method again will overwrite the previous contents.
    The current state may be queried using stateName.
    
    Parameters:
    
    stateFunction - (undocumented)
  - initialize
```
void initialize()
```
    Verify existence of initial state and setup timers. This should be the last call within the constructor, or Actor.preStart() and Actor.postRestart(java.lang.Throwable)
    An initial currentState -> currentState notification will be triggered by calling this method.
    
    See Also:
    
    startWith(S, D, scala.Option<scala.concurrent.duration.FiniteDuration>)
  - stateName
```
S stateName()
```
    Return current state name (i.e. object of type S)
    
    Returns:
    
    (undocumented)
  - stateData
```
D stateData()
```
    Return current state data (i.e. object of type D)
    
    Returns:
    
    (undocumented)
  - nextStateData
```
D nextStateData()
```
    Return next state data (available in onTransition handlers)
    
    Returns:
    
    (undocumented)
  - debugEvent
```
boolean debugEvent()
```
  - currentState_$eq
```
void currentState_$eq(FSM.State<S,D> x$1)
```
  - timeoutFuture_$eq
```
void timeoutFuture_$eq(scala.Option<Cancellable> x$1)
```
  - nextState_$eq
```
void nextState_$eq(FSM.State<S,D> x$1)
```
  - generation_$eq
```
void generation_$eq(long x$1)
```
  - register
```
void register(S name,
              scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> function,
              scala.Option<scala.concurrent.duration.FiniteDuration> timeout)
```
  - handleEvent_$eq
```
void handleEvent_$eq(scala.PartialFunction<FSM.Event<D>,FSM.State<S,D>> x$1)
```
  - terminateEvent_$eq
```
void terminateEvent_$eq(scala.PartialFunction<FSM.StopEvent<S,D>,scala.runtime.BoxedUnit> x$1)
```
  - transitionEvent_$eq
```
void transitionEvent_$eq(scala.collection.immutable.List<scala.PartialFunction<scala.Tuple2<S,S>,scala.runtime.BoxedUnit>> x$1)
```
  - handleTransition
```
void handleTransition(S prev,
                      S next)
```
  - receive
```
scala.PartialFunction<java.lang.Object,scala.runtime.BoxedUnit> receive()
```
    Description copied from interface: Actor
    
    Scala API: This defines the initial actor behavior, it must return a partial function with the actor logic.
    
    Specified by:
    
    receive in interface Actor
    
    Returns:
    
    (undocumented)
  - processMsg
```
void processMsg(java.lang.Object value,
                java.lang.Object source)
```
  - processEvent
```
void processEvent(FSM.Event<D> event,
                  java.lang.Object source)
```
  - applyState
```
void applyState(FSM.State<S,D> nextState)
```
  - makeTransition
```
void makeTransition(FSM.State<S,D> nextState)
```
  - postStop
```
void postStop()
```
    Call onTermination hook; if you want to retain this behavior when overriding make sure to call super.postStop().
    Please note that this method is called by default from preRestart(), so override that one if onTermination shall not be called during restart.
    
    Specified by:
    
    postStop in interface Actor
  - terminate
```
void terminate(FSM.State<S,D> nextState)
```
  - logTermination
```
void logTermination(FSM.Reason reason)
```
    By default FSM.Failure is logged at error level and other reason types are not logged. It is possible to override this behavior.
    
    Parameters:
    
    reason - (undocumented)

Interface FSM<S,​D>

Nested Class Summary

Nested classes/interfaces inherited from interface akka.actor.Actor

Method Summary

Methods inherited from interface akka.actor.Actor

Methods inherited from interface akka.actor.ActorLogging

Methods inherited from interface akka.routing.Listeners

Method Detail

akka$actor$FSM$_setter_$Event_$eq

akka$actor$FSM$_setter_$StopEvent_$eq

akka$actor$FSM$_setter_$StateTimeout_$eq

super$postStop

Event

StopEvent

$minus$greater

StateTimeout

when

when$default$2

startWith

startWith$default$3

stay

stop

stop

stop

transform

startTimerWithFixedDelay

startTimerAtFixedRate

startSingleTimer

setTimer

setTimer$default$4

startTimer

cancelTimer

isTimerActive

setStateTimeout

isStateTimerActive

onTransition

total2pf

onTermination

whenUnhandled

initialize

stateName

stateData

nextStateData

debugEvent

currentState_$eq

timeoutFuture_$eq

nextState_$eq

generation_$eq

register

handleEvent_$eq

terminateEvent_$eq

transitionEvent_$eq

handleTransition

receive

processMsg

processEvent

applyState

makeTransition

postStop

terminate

logTermination

Interface FSM<S,D>