trait Stash extends UnrestrictedStash with RequiresMessageQueue[DequeBasedMessageQueueSemantics]
The Stash trait enables an actor to temporarily stash away messages that can not or
should not be handled using the actor's current behavior.
Example:
class ActorWithProtocol extends Actor with Stash {
def receive = {
case "open" =>
unstashAll()
context.become({
case "write" => // do writing...
case "close" =>
unstashAll()
context.unbecome()
case msg => stash()
}, discardOld = false)
case "done" => // done
case msg => stash()
}
}
Note that the Stash trait can only be used together with actors that have a deque-based
mailbox. By default Stash based actors request a Deque based mailbox since the stash
trait extends RequiresMessageQueue[DequeBasedMessageQueueSemantics].
You can override the default mailbox provided when DequeBasedMessageQueueSemantics are requested via config:
akka.actor.mailbox.requirements {
"akka.dispatch.BoundedDequeBasedMessageQueueSemantics" = your-custom-mailbox
}
Alternatively, you can add your own requirement marker to the actor and configure a mailbox type to be used
for your marker. For a Stash that also enforces unboundedness of the deque see akka.actor.UnboundedStash. For a Stash
that does not enforce any mailbox type see akka.actor.UnrestrictedStash.
Note that the Stash trait must be mixed into (a subclass of) the Actor trait before
any trait/class that overrides the preRestart callback. This means it's not possible to write
Actor with MyActor with Stash if MyActor overrides preRestart.
- Source
- Stash.scala
- Alphabetic
- By Inheritance
- Stash
- RequiresMessageQueue
- UnrestrictedStash
- StashSupport
- Actor
- AnyRef
- Any
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
- Hide All
- Show All
- Public
- All
Type Members
-
type
Receive = PartialFunction[Any, Unit]
- Definition Classes
- Actor
Abstract Value Members
-
abstract
def
receive: Actor.Receive
Scala API: This defines the initial actor behavior, it must return a partial function with the actor logic.
Scala API: This defines the initial actor behavior, it must return a partial function with the actor logic.
- Definition Classes
- Actor
Concrete Value Members
-
final
def
!=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
-
final
def
##(): Int
- Definition Classes
- AnyRef → Any
- def +(other: String): String
- def ->[B](y: B): (Stash, B)
-
final
def
==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
-
def
aroundPostRestart(reason: Throwable): Unit
INTERNAL API.
INTERNAL API.
Can be overridden to intercept calls to
postRestart. CallspostRestartby default.- Attributes
- protected[akka]
- Definition Classes
- Actor
- Annotations
- @InternalApi()
-
def
aroundPostStop(): Unit
INTERNAL API.
INTERNAL API.
Can be overridden to intercept calls to
postStop. CallspostStopby default.- Attributes
- protected[akka]
- Definition Classes
- Actor
- Annotations
- @InternalApi()
-
def
aroundPreRestart(reason: Throwable, message: Option[Any]): Unit
INTERNAL API.
INTERNAL API.
Can be overridden to intercept calls to
preRestart. CallspreRestartby default.- Attributes
- protected[akka]
- Definition Classes
- Actor
- Annotations
- @InternalApi()
-
def
aroundPreStart(): Unit
INTERNAL API.
INTERNAL API.
Can be overridden to intercept calls to
preStart. CallspreStartby default.- Attributes
- protected[akka]
- Definition Classes
- Actor
- Annotations
- @InternalApi()
-
def
aroundReceive(receive: Actor.Receive, msg: Any): Unit
INTERNAL API.
INTERNAL API.
Can be overridden to intercept calls to this actor's current behavior.
- receive
current behavior.
- msg
current message.
- Attributes
- protected[akka]
- Definition Classes
- Actor
- Annotations
- @InternalApi()
-
final
def
asInstanceOf[T0]: T0
- Definition Classes
- Any
-
def
clone(): AnyRef
- Attributes
- protected[java.lang]
- Definition Classes
- AnyRef
- Annotations
- @native() @HotSpotIntrinsicCandidate() @throws( ... )
-
implicit
val
context: ActorContext
Scala API: Stores the context for this actor, including self, and sender.
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!
akka.actor.ActorContext is the Scala API.
getContextreturns a akka.actor.AbstractActor.ActorContext, which is the Java API of the actor context.- Definition Classes
- Actor
- def ensuring(cond: (Stash) ⇒ Boolean, msg: ⇒ Any): Stash
- def ensuring(cond: (Stash) ⇒ Boolean): Stash
- def ensuring(cond: Boolean, msg: ⇒ Any): Stash
- def ensuring(cond: Boolean): Stash
-
final
def
eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
-
def
equals(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- def formatted(fmtstr: String): String
-
final
def
getClass(): Class[_]
- Definition Classes
- AnyRef → Any
- Annotations
- @native() @HotSpotIntrinsicCandidate()
-
def
hashCode(): Int
- Definition Classes
- AnyRef → Any
- Annotations
- @native() @HotSpotIntrinsicCandidate()
-
final
def
isInstanceOf[T0]: Boolean
- Definition Classes
- Any
-
final
def
ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
-
final
def
notify(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native() @HotSpotIntrinsicCandidate()
-
final
def
notifyAll(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native() @HotSpotIntrinsicCandidate()
-
def
postRestart(reason: Throwable): Unit
User overridable callback: By default it calls
preStart().User overridable callback: By default it calls
preStart().- reason
the Throwable that caused the restart to happen Is called right AFTER restart on the newly created Actor to allow reinitialization after an Actor crash.
- Definition Classes
- Actor
- Annotations
- @throws( classOf[Exception] )
-
def
postStop(): Unit
Overridden callback.
Overridden callback. Prepends all messages in the stash to the mailbox and clears the stash. Must be called when overriding this method, otherwise stashed messages won't be propagated to DeadLetters when actor stops.
- Definition Classes
- UnrestrictedStash → Actor
- Annotations
- @throws( classOf[Exception] )
-
def
preRestart(reason: Throwable, message: Option[Any]): Unit
Overridden callback.
Overridden callback. Prepends all messages in the stash to the mailbox, clears the stash, stops all children and invokes the postStop() callback.
- reason
the Throwable that caused the restart to happen
- message
optionally the current message the actor processed when failing, if applicable Is called on a crashed Actor right BEFORE it is restarted to allow clean up of resources before Actor is terminated.
- Definition Classes
- UnrestrictedStash → Actor
- Annotations
- @throws( classOf[Exception] )
-
def
preStart(): Unit
User overridable callback.
User overridable callback.
Is called when an Actor is started. Actors are automatically started asynchronously when created. Empty default implementation.
- Definition Classes
- Actor
- Annotations
- @throws( classOf[Exception] )
-
implicit final
val
self: ActorRef
The 'self' field holds the ActorRef for this actor.
The 'self' field holds the ActorRef for this actor.
Can be used to send messages to itself:
self ! message
- Definition Classes
- Actor
-
final
def
sender(): ActorRef
The reference sender Actor of the last received message.
The reference sender Actor of the last received message. Is defined if the message was sent from another Actor, else
deadLettersin akka.actor.ActorSystem.WARNING: Only valid within the Actor itself, so do not close over it and publish it to other threads!
- Definition Classes
- Actor
-
def
stash(): Unit
Adds the current message (the message that the actor received last) to the actor's stash.
Adds the current message (the message that the actor received last) to the actor's stash.
- Definition Classes
- StashSupport
- Exceptions thrown
IllegalStateExceptionif the same message is stashed more than onceStashOverflowExceptionin case of a stash capacity violation
-
def
supervisorStrategy: SupervisorStrategy
User overridable definition the strategy to use for supervising child actors.
User overridable definition the strategy to use for supervising child actors.
- Definition Classes
- Actor
-
final
def
synchronized[T0](arg0: ⇒ T0): T0
- Definition Classes
- AnyRef
-
def
toString(): String
- Definition Classes
- AnyRef → Any
-
def
unhandled(message: Any): Unit
User overridable callback.
User overridable callback.
Is called when a message isn't handled by the current behavior of the actor by default it fails with either a akka.actor.DeathPactException (in case of an unhandled akka.actor.Terminated message) or publishes an akka.actor.UnhandledMessage to the actor's system's akka.event.EventStream
- Definition Classes
- Actor
-
def
unstashAll(): Unit
Prepends all messages in the stash to the mailbox, and then clears the stash.
Prepends all messages in the stash to the mailbox, and then clears the stash.
Messages from the stash are enqueued to the mailbox until the capacity of the mailbox (if any) has been reached. In case a bounded mailbox overflows, a
MessageQueueAppendFailedExceptionis thrown.The stash is guaranteed to be empty after calling
unstashAll().- Definition Classes
- StashSupport
-
final
def
wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
-
final
def
wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @native() @throws( ... )
-
final
def
wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws( ... )
- def →[B](y: B): (Stash, B)