Package akka.actor

Class AbstractFSM<S,​D>

  • All Implemented Interfaces:
    Actor, ActorLogging, FSM<S,​D>, Listeners
    Direct Known Subclasses:
    AbstractFSMWithStash, AbstractLoggingFSM

    public abstract class AbstractFSM<S,​D>
    extends java.lang.Object
    implements FSM<S,​D>
    Returns this AbstractActor's ActorContext The ActorContext is not thread safe so do not expose it outside of the AbstractActor.
    • Constructor Detail

      • AbstractFSM

        public AbstractFSM()
    • Method Detail

      • NullFunction

        public static <S,​D> scala.PartialFunction<S,​D> NullFunction()
      • $minus$greater

        public FSM.$minus$greater$ $minus$greater()
        Description copied from interface: FSM
        This extractor is just convenience for matching a (S, S) pair, including a reminder what the new state is.
        Specified by:
        $minus$greater in interface FSM<S,​D>
        Returns:
        (undocumented)
      • StateTimeout

        public FSM.StateTimeout$ StateTimeout()
        Description copied from interface: FSM
        This case object is received in case of a state timeout.
        Specified by:
        StateTimeout in interface FSM<S,​D>
        Returns:
        (undocumented)
      • akka$actor$FSM$_setter_$StateTimeout_$eq

        protected void akka$actor$FSM$_setter_$StateTimeout_$eq​(FSM.StateTimeout$ x$1)
        Description copied from interface: FSM
        This case object is received in case of a state timeout.
        Specified by:
        akka$actor$FSM$_setter_$StateTimeout_$eq in interface FSM<S,​D>
        Parameters:
        x$1 - (undocumented)
      • context

        public ActorContext context()
        Description copied from interface: Actor
        Scala API: Stores the context for this actor, including self, and sender. It is implicit to support operations such as forward.

        WARNING: Only valid within the Actor itself, so do not close over it and publish it to other threads!

        ActorContext is the Scala API. getContext returns a AbstractActor.ActorContext, which is the Java API of the actor context.

        Specified by:
        context in interface Actor
        Returns:
        (undocumented)
      • self

        public final ActorRef self()
        Description copied from interface: Actor
        The 'self' field holds the ActorRef for this actor.

        Can be used to send messages to itself:
         self ! message
         
        Specified by:
        self in interface Actor
        Returns:
        (undocumented)
      • akka$actor$Actor$_setter_$self_$eq

        protected final void akka$actor$Actor$_setter_$self_$eq​(ActorRef x$1)
        Description copied from interface: Actor
        The 'self' field holds the ActorRef for this actor.

        Can be used to send messages to itself:
         self ! message
         
        Specified by:
        akka$actor$Actor$_setter_$self_$eq in interface Actor
        Parameters:
        x$1 - (undocumented)
      • getSelf

        public ActorRef getSelf()
        Returns the ActorRef for this actor.

        Same as self().

        Returns:
        (undocumented)
      • getSender

        public ActorRef getSender()
        The reference sender Actor of the currently processed message. This is always a legal destination to send to, even if there is no logical recipient for the reply, in which case it will be sent to the dead letter mailbox.

        Same as sender().

        WARNING: Only valid within the Actor itself, so do not close over it and publish it to other threads!

        Returns:
        (undocumented)
      • when

        public final void when​(S stateName,
                               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.

        Parameters:
        stateName - designator for the state
        stateFunction - partial function describing response to input
      • when

        public final void when​(S stateName,
                               FSMStateFunctionBuilder<S,​D> stateFunctionBuilder)
        Insert a new StateFunction at the end of the processing chain for the given state.

        Parameters:
        stateName - designator for the state
        stateFunctionBuilder - partial function builder describing response to input
      • when

        public final void when​(S stateName,
                               scala.concurrent.duration.FiniteDuration stateTimeout,
                               FSMStateFunctionBuilder<S,​D> stateFunctionBuilder)
        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
        stateFunctionBuilder - partial function builder describing response to input
      • when

        public final void when​(S stateName,
                               java.time.Duration stateTimeout,
                               FSMStateFunctionBuilder<S,​D> stateFunctionBuilder)
        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
        stateFunctionBuilder - partial function builder describing response to input
      • startWith

        public final void startWith​(S stateName,
                                    D stateData,
                                    scala.concurrent.duration.FiniteDuration timeout)
        Set initial state. Call this method from the constructor before the FSM.initialize() method. If different state is needed after a restart this method, followed by FSM.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

        public final void startWith​(S stateName,
                                    D stateData,
                                    java.time.Duration timeout)
        Set initial state. Call this method from the constructor before the FSM.initialize() method. If different state is needed after a restart this method, followed by FSM.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
      • onTransition

        public final void onTransition​(FSMTransitionHandlerBuilder<S> transitionHandlerBuilder)
        Add a handler which is called upon each state transition, i.e. not when staying in the same state.

        Multiple handlers may be installed, and every one of them will be called, not only the first one matching.

        Parameters:
        transitionHandlerBuilder - (undocumented)
      • onTransition

        public final void onTransition​(FI.UnitApply2<S,​S> transitionHandler)
        Add a handler which is called upon each state transition, i.e. not when staying in the same state.

        Multiple handlers may be installed, and every one of them will be called, not only the first one matching.

        Parameters:
        transitionHandler - (undocumented)
      • whenUnhandled

        public final void whenUnhandled​(FSMStateFunctionBuilder<S,​D> stateFunctionBuilder)
        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:
        stateFunctionBuilder - (undocumented)
      • onTermination

        public final void onTermination​(FSMStopBuilder<S,​D> stopBuilder)
        Set handler which is called upon termination of this FSM actor. Calling this method again will overwrite the previous contents.
        Parameters:
        stopBuilder - (undocumented)
      • matchEvent

        public final <ET,​DT extends DFSMStateFunctionBuilder<S,​D> matchEvent​(java.lang.Class<ET> eventType,
                                                                                           java.lang.Class<DT> dataType,
                                                                                           FI.TypedPredicate2<ET,​DT> predicate,
                                                                                           FI.Apply2<ET,​DT,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches on an event and data type and a predicate.

        Parameters:
        eventType - the event type to match on
        dataType - the data type to match on
        predicate - a predicate to evaluate on the matched types
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchEvent

        public final <ET,​DT extends DFSMStateFunctionBuilder<S,​D> matchEvent​(java.lang.Class<ET> eventType,
                                                                                           java.lang.Class<DT> dataType,
                                                                                           FI.Apply2<ET,​DT,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches on an event and data type.

        Parameters:
        eventType - the event type to match on
        dataType - the data type to match on
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchEvent

        public final <ET> FSMStateFunctionBuilder<S,​D> matchEvent​(java.lang.Class<ET> eventType,
                                                                        FI.TypedPredicate2<ET,​D> predicate,
                                                                        FI.Apply2<ET,​D,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches if the event type and predicate matches.

        Parameters:
        eventType - the event type to match on
        predicate - a predicate that will be evaluated on the data and the event
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchEvent

        public final <ET> FSMStateFunctionBuilder<S,​D> matchEvent​(java.lang.Class<ET> eventType,
                                                                        FI.Apply2<ET,​D,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches if the event type matches.

        Parameters:
        eventType - the event type to match on
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchEvent

        public final FSMStateFunctionBuilder<S,​D> matchEvent​(FI.TypedPredicate2<java.lang.Object,​D> predicate,
                                                                   FI.Apply2<java.lang.Object,​D,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches if the predicate matches.

        Parameters:
        predicate - a predicate that will be evaluated on the data and the event
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchEvent

        public final <DT extends DFSMStateFunctionBuilder<S,​D> matchEvent​(java.util.List<java.lang.Object> eventMatches,
                                                                                  java.lang.Class<DT> dataType,
                                                                                  FI.Apply2<java.lang.Object,​DT,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches on the data type and if any of the event types in the list match or any of the event instances in the list compares equal.

        Parameters:
        eventMatches - a list of types or instances to match against
        dataType - the data type to match on
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchEvent

        public final FSMStateFunctionBuilder<S,​D> matchEvent​(java.util.List<java.lang.Object> eventMatches,
                                                                   FI.Apply2<java.lang.Object,​D,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches if any of the event types in the list match or any of the event instances in the list compares equal.

        Parameters:
        eventMatches - a list of types or instances to match against
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchEventEquals

        public final <E,​DT extends DFSMStateFunctionBuilder<S,​D> matchEventEquals​(E event,
                                                                                                java.lang.Class<DT> dataType,
                                                                                                FI.Apply2<E,​DT,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches on the data type and if the event compares equal.

        Parameters:
        event - an event to compare equal against
        dataType - the data type to match on
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchEventEquals

        public final <E> FSMStateFunctionBuilder<S,​D> matchEventEquals​(E event,
                                                                             FI.Apply2<E,​D,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches if the event compares equal.

        Parameters:
        event - an event to compare equal against
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchAnyEvent

        public final FSMStateFunctionBuilder<S,​D> matchAnyEvent​(FI.Apply2<java.lang.Object,​D,​FSM.State<S,​D>> apply)
        Create an FSMStateFunctionBuilder with the first case statement set.

        A case statement that matches on any type of event.

        Parameters:
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchState

        public final FSMTransitionHandlerBuilder<S> matchState​(S fromState,
                                                               S toState,
                                                               FI.UnitApplyVoid apply)
        Create an FSMTransitionHandlerBuilder with the first case statement set.

        A case statement that matches on a from state and a to state.

        Parameters:
        fromState - the from state to match on
        toState - the to state to match on
        apply - an action to apply when the states match
        Returns:
        the builder with the case statement added
      • matchState

        public final FSMTransitionHandlerBuilder<S> matchState​(S fromState,
                                                               S toState,
                                                               FI.UnitApply2<S,​S> apply)
        Create an FSMTransitionHandlerBuilder with the first case statement set.

        A case statement that matches on a from state and a to state.

        Parameters:
        fromState - the from state to match on
        toState - the to state to match on
        apply - an action to apply when the states match
        Returns:
        the builder with the case statement added
      • matchStop

        public final FSMStopBuilder<S,​D> matchStop​(FSM.Reason reason,
                                                         FI.UnitApply2<S,​D> apply)
        Create an FSMStopBuilder with the first case statement set.

        A case statement that matches on an FSM.Reason.

        Parameters:
        reason - the reason for the termination
        apply - an action to apply to the event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchStop

        public final <RT extends FSM.ReasonFSMStopBuilder<S,​D> matchStop​(java.lang.Class<RT> reasonType,
                                                                                 FI.UnitApply3<RT,​S,​D> apply)
        Create an FSMStopBuilder with the first case statement set.

        A case statement that matches on a reason type.

        Parameters:
        reasonType - the reason type to match on
        apply - an action to apply to the reason, event and state data if there is a match
        Returns:
        the builder with the case statement added
      • matchStop

        public final <RT extends FSM.ReasonFSMStopBuilder<S,​D> matchStop​(java.lang.Class<RT> reasonType,
                                                                                 FI.TypedPredicate<RT> predicate,
                                                                                 FI.UnitApply3<RT,​S,​D> apply)
        Create an FSMStopBuilder with the first case statement set.

        A case statement that matches on a reason type and a predicate.

        Parameters:
        reasonType - the reason type to match on
        apply - an action to apply to the reason, event and state data if there is a match
        predicate - a predicate that will be evaluated on the reason if the type matches
        Returns:
        the builder with the case statement added
      • matchData

        public final <DT extends DUnitPFBuilder<D> matchData​(java.lang.Class<DT> dataType,
                                                               FI.UnitApply<DT> apply)
        Create a UnitPFBuilder with the first case statement set.

        Parameters:
        dataType - a type to match the argument against
        apply - an action to apply to the argument if the type matches
        Returns:
        a builder with the case statement added
      • matchData

        public final <DT extends DUnitPFBuilder<D> matchData​(java.lang.Class<DT> dataType,
                                                               FI.TypedPredicate<DT> predicate,
                                                               FI.UnitApply<DT> apply)
        Create a UnitPFBuilder with the first case statement set.

        Parameters:
        dataType - a type to match the argument against
        predicate - a predicate that will be evaluated on the argument if the type matches
        apply - an action to apply to the argument if the type and predicate matches
        Returns:
        a builder with the case statement added
      • goTo

        public final FSM.State<S,​D> goTo​(S nextStateName)
        Produce transition to other state. Return this from a state function in order to effect the transition.

        Parameters:
        nextStateName - state designator for the next state
        Returns:
        state transition descriptor
      • startTimerWithFixedDelay

        public void startTimerWithFixedDelay​(java.lang.String name,
                                             java.lang.Object msg,
                                             java.time.Duration 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 and it's guaranteed that a message from the previous timer is not received, even though it might already be enqueued in the mailbox when the new timer is started.

        Parameters:
        name - (undocumented)
        msg - (undocumented)
        delay - (undocumented)
      • startTimerAtFixedRate

        public void startTimerAtFixedRate​(java.lang.String name,
                                          java.lang.Object msg,
                                          java.time.Duration 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 and it's guaranteed that a message from the previous timer is not received, even though it might already be enqueued in the mailbox when the new timer is started.

        Parameters:
        name - (undocumented)
        msg - (undocumented)
        interval - (undocumented)
      • startSingleTimer

        public void startSingleTimer​(java.lang.String name,
                                     java.lang.Object msg,
                                     java.time.Duration 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 and it's guaranteed that a message from the previous timer is not received, even though it might already be enqueued in the mailbox when the new timer is started.

        Parameters:
        name - (undocumented)
        msg - (undocumented)
        delay - (undocumented)
      • setTimer

        public final void setTimer​(java.lang.String name,
                                   java.lang.Object msg,
                                   scala.concurrent.duration.FiniteDuration timeout)
        Deprecated.
        Use startSingleTimer instead. 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
      • setTimer

        public final void setTimer​(java.lang.String name,
                                   java.lang.Object msg,
                                   java.time.Duration timeout)
        Deprecated.
        Use startSingleTimer instead. 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
      • setTimer

        public final void setTimer​(java.lang.String name,
                                   java.lang.Object msg,
                                   java.time.Duration 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
      • Normal

        public FSM.Reason Normal()
        Default reason if calling stop().
        Returns:
        (undocumented)
      • Shutdown

        public FSM.Reason Shutdown()
        Reason given when someone was calling system.stop(fsm) from outside; also applies to Stop supervision directive.
        Returns:
        (undocumented)