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Renamed more things to SupervisorStrategy. Updated more docs. See #1711

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This commit is contained in:
Patrik Nordwall 2012-01-23 17:18:49 +01:00
parent 66e0a7cf0b
commit 9e15d2062b
19 changed files with 166 additions and 148 deletions
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4
akka-actor-tests/src/test/scala/akka/actor/DeathWatchSpec.scala
View file

@ -23,7 +23,7 @@ trait DeathWatchSpec { this: AkkaSpec with ImplicitSender with DefaultTimeout
import DeathWatchSpec._
lazy val supervisor = system.actorOf(Props(new Supervisor(FaultHandlingStrategy.defaultFaultHandler)), "watchers")
lazy val supervisor = system.actorOf(Props(new Supervisor(SupervisorStrategy.defaultStrategy)), "watchers")
def startWatching(target: ActorRef) = Await.result((supervisor ? props(target, testActor)).mapTo[ActorRef], 3 seconds)
@ -115,7 +115,7 @@ trait DeathWatchSpec { this: AkkaSpec with ImplicitSender with DefaultTimeout
"fail a monitor which does not handle Terminated()" in {
filterEvents(EventFilter[ActorKilledException](), EventFilter[DeathPactException]()) {
case class FF(fail: Failed)
val strategy = new OneForOneStrategy(FaultHandlingStrategy.makeDecider(List(classOf[Exception])), Some(0)) {
val strategy = new OneForOneStrategy(SupervisorStrategy.makeDecider(List(classOf[Exception])), Some(0)) {
override def handleFailure(context: ActorContext, child: ActorRef, cause: Throwable, stats: ChildRestartStats, children: Iterable[ChildRestartStats]) = {
testActor.tell(FF(Failed(cause)), child)
super.handleFailure(context, child, cause, stats, children)

2
akka-actor-tests/src/test/scala/akka/actor/Supervisor.scala
View file

@ -7,7 +7,7 @@ package akka.actor
* For testing Supervisor behavior, normally you don't supply the strategy
* from the outside like this.
*/
class Supervisor(override val supervisorStrategy: FaultHandlingStrategy) extends Actor {
class Supervisor(override val supervisorStrategy: SupervisorStrategy) extends Actor {
def receive = {
case x: Props ⇒ sender ! context.actorOf(x)

6
akka-actor-tests/src/test/scala/akka/actor/SupervisorHierarchySpec.scala
View file

@ -16,7 +16,7 @@ object SupervisorHierarchySpec {
* For testing Supervisor behavior, normally you don't supply the strategy
* from the outside like this.
*/
class CountDownActor(countDown: CountDownLatch, override val supervisorStrategy: FaultHandlingStrategy) extends Actor {
class CountDownActor(countDown: CountDownLatch, override val supervisorStrategy: SupervisorStrategy) extends Actor {
protected def receive = {
case p: Props ⇒ sender ! context.actorOf(p)
@ -43,7 +43,7 @@ class SupervisorHierarchySpec extends AkkaSpec with DefaultTimeout {
val managerProps = Props(new CountDownActor(countDown, AllForOneStrategy(List(), None, None)))
val manager = Await.result((boss ? managerProps).mapTo[ActorRef], timeout.duration)
val workerProps = Props(new CountDownActor(countDown, FaultHandlingStrategy.defaultFaultHandler))
val workerProps = Props(new CountDownActor(countDown, SupervisorStrategy.defaultStrategy))
val workerOne, workerTwo, workerThree = Await.result((manager ? workerProps).mapTo[ActorRef], timeout.duration)
filterException[ActorKilledException] {
@ -62,7 +62,7 @@ class SupervisorHierarchySpec extends AkkaSpec with DefaultTimeout {
val boss = system.actorOf(Props(new Actor {
override val supervisorStrategy = OneForOneStrategy(List(classOf[Throwable]), 1, 5000)
val crasher = context.watch(context.actorOf(Props(new CountDownActor(countDownMessages, FaultHandlingStrategy.defaultFaultHandler))))
val crasher = context.watch(context.actorOf(Props(new CountDownActor(countDownMessages, SupervisorStrategy.defaultStrategy))))
protected def receive = {
case "killCrasher" ⇒ crasher ! Kill

2
akka-actor-tests/src/test/scala/akka/actor/TypedActorSpec.scala
View file

@ -300,7 +300,7 @@ class TypedActorSpec extends AkkaSpec(TypedActorSpec.config)
filterEvents(EventFilter[IllegalStateException]("expected")) {
val boss = system.actorOf(Props(new Actor {
override val supervisorStrategy = OneForOneStrategy {
case e: IllegalStateException if e.getMessage == "expected" ⇒ FaultHandlingStrategy.Resume
case e: IllegalStateException if e.getMessage == "expected" ⇒ SupervisorStrategy.Resume
}
def receive = {
case p: TypedProps[_] ⇒ context.sender ! TypedActor(context).typedActorOf(p)

2
akka-actor/src/main/scala/akka/actor/Actor.scala
View file

@ -236,7 +236,7 @@ trait Actor {
* User overridable definition the strategy to use for supervising
* child actors.
*/
def supervisorStrategy(): FaultHandlingStrategy = FaultHandlingStrategy.defaultFaultHandler
def supervisorStrategy(): SupervisorStrategy = SupervisorStrategy.defaultStrategy
/**
* User overridable callback.

6
akka-actor/src/main/scala/akka/actor/ActorRefProvider.scala
View file

@ -336,7 +336,7 @@ class LocalActorRefProvider(
private class Guardian extends Actor {
override val supervisorStrategy = {
import akka.actor.FaultHandlingStrategy._
import akka.actor.SupervisorStrategy._
OneForOneStrategy {
case _: ActorKilledException ⇒ Stop
case _: ActorInitializationException ⇒ Stop
@ -376,8 +376,6 @@ class LocalActorRefProvider(
override def preRestart(cause: Throwable, msg: Option[Any]) {}
}
private val guardianProps = Props(new Guardian)
/*
* The problem is that ActorRefs need a reference to the ActorSystem to
* provide their service. Hence they cannot be created while the
@ -403,6 +401,8 @@ class LocalActorRefProvider(
*/
def registerExtraNames(_extras: Map[String, InternalActorRef]): Unit = extraNames ++= _extras
private val guardianProps = Props(new Guardian)
lazy val rootGuardian: InternalActorRef =
new LocalActorRef(system, guardianProps, theOneWhoWalksTheBubblesOfSpaceTime, rootPath, true) {
object Extra {

44
akka-actor/src/main/scala/akka/actor/FaultHandling.scala
View file

@ -44,7 +44,7 @@ case class ChildRestartStats(val child: ActorRef, var maxNrOfRetriesCount: Int =
}
}
object FaultHandlingStrategy {
object SupervisorStrategy {
sealed trait Action
/**
@ -95,7 +95,7 @@ object FaultHandlingStrategy {
*/
def escalate = Escalate
final val defaultFaultHandler: FaultHandlingStrategy = {
final val defaultStrategy: SupervisorStrategy = {
def defaultDecider: Decider = {
case _: ActorInitializationException ⇒ Stop
case _: ActorKilledException ⇒ Stop
@ -158,9 +158,9 @@ object FaultHandlingStrategy {
}
}
abstract class FaultHandlingStrategy {
abstract class SupervisorStrategy {
import FaultHandlingStrategy._
import SupervisorStrategy._
def decider: Decider
@ -200,12 +200,12 @@ abstract class FaultHandlingStrategy {
object AllForOneStrategy {
def apply(trapExit: List[Class[_ <: Throwable]], maxNrOfRetries: Int, withinTimeRange: Int): AllForOneStrategy =
new AllForOneStrategy(FaultHandlingStrategy.makeDecider(trapExit),
new AllForOneStrategy(SupervisorStrategy.makeDecider(trapExit),
if (maxNrOfRetries < 0) None else Some(maxNrOfRetries), if (withinTimeRange < 0) None else Some(withinTimeRange))
def apply(trapExit: List[Class[_ <: Throwable]], maxNrOfRetries: Option[Int], withinTimeRange: Option[Int]): AllForOneStrategy =
new AllForOneStrategy(FaultHandlingStrategy.makeDecider(trapExit), maxNrOfRetries, withinTimeRange)
new AllForOneStrategy(SupervisorStrategy.makeDecider(trapExit), maxNrOfRetries, withinTimeRange)
def apply(trapExit: List[Class[_ <: Throwable]], maxNrOfRetries: Option[Int]): AllForOneStrategy =
new AllForOneStrategy(FaultHandlingStrategy.makeDecider(trapExit), maxNrOfRetries, None)
new AllForOneStrategy(SupervisorStrategy.makeDecider(trapExit), maxNrOfRetries, None)
}
/**
@ -214,22 +214,22 @@ object AllForOneStrategy {
* maxNrOfRetries = the number of times an actor is allowed to be restarted
* withinTimeRange = millisecond time window for maxNrOfRetries, negative means no window
*/
case class AllForOneStrategy(decider: FaultHandlingStrategy.Decider,
case class AllForOneStrategy(decider: SupervisorStrategy.Decider,
maxNrOfRetries: Option[Int] = None,
withinTimeRange: Option[Int] = None) extends FaultHandlingStrategy {
withinTimeRange: Option[Int] = None) extends SupervisorStrategy {
def this(decider: FaultHandlingStrategy.JDecider, maxNrOfRetries: Int, withinTimeRange: Int) =
this(FaultHandlingStrategy.makeDecider(decider),
def this(decider: SupervisorStrategy.JDecider, maxNrOfRetries: Int, withinTimeRange: Int) =
this(SupervisorStrategy.makeDecider(decider),
if (maxNrOfRetries < 0) None else Some(maxNrOfRetries),
if (withinTimeRange < 0) None else Some(withinTimeRange))
def this(trapExit: JIterable[Class[_ <: Throwable]], maxNrOfRetries: Int, withinTimeRange: Int) =
this(FaultHandlingStrategy.makeDecider(trapExit),
this(SupervisorStrategy.makeDecider(trapExit),
if (maxNrOfRetries < 0) None else Some(maxNrOfRetries),
if (withinTimeRange < 0) None else Some(withinTimeRange))
def this(trapExit: Array[Class[_ <: Throwable]], maxNrOfRetries: Int, withinTimeRange: Int) =
this(FaultHandlingStrategy.makeDecider(trapExit),
this(SupervisorStrategy.makeDecider(trapExit),
if (maxNrOfRetries < 0) None else Some(maxNrOfRetries),
if (withinTimeRange < 0) None else Some(withinTimeRange))
@ -257,12 +257,12 @@ case class AllForOneStrategy(decider: FaultHandlingStrategy.Decider,
object OneForOneStrategy {
def apply(trapExit: List[Class[_ <: Throwable]], maxNrOfRetries: Int, withinTimeRange: Int): OneForOneStrategy =
new OneForOneStrategy(FaultHandlingStrategy.makeDecider(trapExit),
new OneForOneStrategy(SupervisorStrategy.makeDecider(trapExit),
if (maxNrOfRetries < 0) None else Some(maxNrOfRetries), if (withinTimeRange < 0) None else Some(withinTimeRange))
def apply(trapExit: List[Class[_ <: Throwable]], maxNrOfRetries: Option[Int], withinTimeRange: Option[Int]): OneForOneStrategy =
new OneForOneStrategy(FaultHandlingStrategy.makeDecider(trapExit), maxNrOfRetries, withinTimeRange)
new OneForOneStrategy(SupervisorStrategy.makeDecider(trapExit), maxNrOfRetries, withinTimeRange)
def apply(trapExit: List[Class[_ <: Throwable]], maxNrOfRetries: Option[Int]): OneForOneStrategy =
new OneForOneStrategy(FaultHandlingStrategy.makeDecider(trapExit), maxNrOfRetries, None)
new OneForOneStrategy(SupervisorStrategy.makeDecider(trapExit), maxNrOfRetries, None)
}
/**
@ -271,22 +271,22 @@ object OneForOneStrategy {
* maxNrOfRetries = the number of times an actor is allowed to be restarted
* withinTimeRange = millisecond time window for maxNrOfRetries, negative means no window
*/
case class OneForOneStrategy(decider: FaultHandlingStrategy.Decider,
case class OneForOneStrategy(decider: SupervisorStrategy.Decider,
maxNrOfRetries: Option[Int] = None,
withinTimeRange: Option[Int] = None) extends FaultHandlingStrategy {
withinTimeRange: Option[Int] = None) extends SupervisorStrategy {
def this(decider: FaultHandlingStrategy.JDecider, maxNrOfRetries: Int, withinTimeRange: Int) =
this(FaultHandlingStrategy.makeDecider(decider),
def this(decider: SupervisorStrategy.JDecider, maxNrOfRetries: Int, withinTimeRange: Int) =
this(SupervisorStrategy.makeDecider(decider),
if (maxNrOfRetries < 0) None else Some(maxNrOfRetries),
if (withinTimeRange < 0) None else Some(withinTimeRange))
def this(trapExit: JIterable[Class[_ <: Throwable]], maxNrOfRetries: Int, withinTimeRange: Int) =
this(FaultHandlingStrategy.makeDecider(trapExit),
this(SupervisorStrategy.makeDecider(trapExit),
if (maxNrOfRetries < 0) None else Some(maxNrOfRetries),
if (withinTimeRange < 0) None else Some(withinTimeRange))
def this(trapExit: Array[Class[_ <: Throwable]], maxNrOfRetries: Int, withinTimeRange: Int) =
this(FaultHandlingStrategy.makeDecider(trapExit),
this(SupervisorStrategy.makeDecider(trapExit),
if (maxNrOfRetries < 0) None else Some(maxNrOfRetries),
if (withinTimeRange < 0) None else Some(withinTimeRange))

10
akka-actor/src/main/scala/akka/actor/TypedActor.scala
View file

@ -218,9 +218,9 @@ object TypedActor extends ExtensionId[TypedActorExtension] with ExtensionIdProvi
TypedActor.currentContext set null
}
override def supervisorStrategy: FaultHandlingStrategy = me match {
case l: SupervisorStrategy ⇒ l.supervisorStrategy
case _ ⇒ super.supervisorStrategy
override def supervisorStrategy(): SupervisorStrategy = me match {
case l: Supervisor ⇒ l.supervisorStrategy
case _ ⇒ super.supervisorStrategy
}
override def preStart(): Unit = me match {
@ -283,12 +283,12 @@ object TypedActor extends ExtensionId[TypedActorExtension] with ExtensionIdProvi
/**
* Mix this into your TypedActor to be able to define supervisor strategy
*/
trait SupervisorStrategy {
trait Supervisor {
/**
* User overridable definition the strategy to use for supervising
* child actors.
*/
def supervisorStrategy: FaultHandlingStrategy = FaultHandlingStrategy.defaultFaultHandler
def supervisorStrategy(): SupervisorStrategy = SupervisorStrategy.defaultStrategy
}
/**

6
akka-actor/src/main/scala/akka/actor/UntypedActor.scala
View file

@ -37,7 +37,7 @@ import akka.dispatch.{ MessageDispatcher, Promise }
* }
* }
*
* private static FaultHandlingStrategy strategy = new OneForOneStrategy(new Function<Throwable, Action>() {
* private static SupervisorStrategy strategy = new OneForOneStrategy(new Function<Throwable, Action>() {
* @Override
* public Action apply(Throwable t) {
* if (t instanceof ArithmeticException) {
@ -53,7 +53,7 @@ import akka.dispatch.{ MessageDispatcher, Promise }
* }, 10, 60000);
*
* @Override
* public FaultHandlingStrategy supervisorStrategy() {
* public SupervisorStrategy supervisorStrategy() {
* return strategy;
* }
*
@ -116,7 +116,7 @@ abstract class UntypedActor extends Actor {
* User overridable definition the strategy to use for supervising
* child actors.
*/
override def supervisorStrategy(): FaultHandlingStrategy = super.supervisorStrategy()
override def supervisorStrategy(): SupervisorStrategy = super.supervisorStrategy()
/**
* User overridable callback.

154
akka-docs/general/actors.rst
View file

@ -3,123 +3,121 @@
What is an Actor?
=================
The previous section about :ref:`actor-systems` explained how actors form
hierarchies and are the smallest unit when building an application. This
section looks at one such actor in isolation, explaining the concepts you
encounter while implementing it. For more an in depth reference with all the
The previous section about :ref:`actor-systems` explained how actors form
hierarchies and are the smallest unit when building an application. This
section looks at one such actor in isolation, explaining the concepts you
encounter while implementing it. For more an in depth reference with all the
details please refer to :ref:`actors-scala` and :ref:`untyped-actors-java`.
An actor is a container for `State`_, `Behavior`_, a `Mailbox`_, `Children`_
and a `Fault Handling Strategy`_. All of this is encapsulated behind an `Actor
An actor is a container for `State`_, `Behavior`_, a `Mailbox`_, `Children`_
and a `Supervisor Strategy`_. All of this is encapsulated behind an `Actor
Reference`_. Finally, this happens `When an Actor Terminates`_.
Actor Reference
---------------
As detailed below, an actor object needs to be shielded from the outside in
order to benefit from the actor model. Therefore, actors are represented to the
outside using actor references, which are objects that can be passed around
freely and without restriction. This split into inner and outer object enables
transparency for all the desired operations: restarting an actor without
needing to update references elsewhere, placing the actual actor object on
remote hosts, sending messages to actors in completely different applications.
But the most important aspect is that it is not possible to look inside an
actor and get hold of its state from the outside, unless the actor unwisely
As detailed below, an actor object needs to be shielded from the outside in
order to benefit from the actor model. Therefore, actors are represented to the
outside using actor references, which are objects that can be passed around
freely and without restriction. This split into inner and outer object enables
transparency for all the desired operations: restarting an actor without
needing to update references elsewhere, placing the actual actor object on
remote hosts, sending messages to actors in completely different applications.
But the most important aspect is that it is not possible to look inside an
actor and get hold of its state from the outside, unless the actor unwisely
publishes this information itself.
State
-----
Actor objects will typically contain some variables which reflect possible
states the actor may be in. This can be an explicit state machine (e.g. using
the :ref:`fsm` module), or it could be a counter, set of listeners, pending
requests, etc. These data are what make an actor valuable, and they must be
protected from corruption by other actors. The good news is that Akka actors
conceptually each have their own light-weight thread, which is completely
shielded from the rest of the system. This means that instead of having to
synchronize access using locks you can just write your actor code without
Actor objects will typically contain some variables which reflect possible
states the actor may be in. This can be an explicit state machine (e.g. using
the :ref:`fsm` module), or it could be a counter, set of listeners, pending
requests, etc. These data are what make an actor valuable, and they must be
protected from corruption by other actors. The good news is that Akka actors
conceptually each have their own light-weight thread, which is completely
shielded from the rest of the system. This means that instead of having to
synchronize access using locks you can just write your actor code without
worrying about concurrency at all.
Behind the scenes Akka will run sets of actors on sets of real threads, where
typically many actors share one thread, and subsequent invocations of one actor
may end up being processed on different threads. Akka ensures that this
implementation detail does not affect the single-threadedness of handling the
Behind the scenes Akka will run sets of actors on sets of real threads, where
typically many actors share one thread, and subsequent invocations of one actor
may end up being processed on different threads. Akka ensures that this
implementation detail does not affect the single-threadedness of handling the
actor’s state.
Because the internal state is vital to an actor’s operations, having
inconsistent state is fatal. Thus, when the actor fails and is restarted by its
supervisor, the state will be created from scratch, like upon first creating
Because the internal state is vital to an actor’s operations, having
inconsistent state is fatal. Thus, when the actor fails and is restarted by its
supervisor, the state will be created from scratch, like upon first creating
the actor. This is to enable the ability of self-healing of the system.
Behavior
--------
Every time a message is processed, it is matched against the current behavior
of the actor. Behavior means a function which defines the actions to be taken
in reaction to the message at that point in time, say forward a request if the
client is authorized, deny it otherwise. This behavior may change over time,
e.g. because different clients obtain authorization over time, or because the
actor may go into an “out-of-service” mode and later come back. These changes
are achieved by either encoding them in state variables which are read from the
behavior logic, or the function itself may be swapped out at runtime, see the
``become`` and ``unbecome`` operations. However, the initial behavior defined
during construction of the actor object is special in the sense that a restart
Every time a message is processed, it is matched against the current behavior
of the actor. Behavior means a function which defines the actions to be taken
in reaction to the message at that point in time, say forward a request if the
client is authorized, deny it otherwise. This behavior may change over time,
e.g. because different clients obtain authorization over time, or because the
actor may go into an “out-of-service” mode and later come back. These changes
are achieved by either encoding them in state variables which are read from the
behavior logic, or the function itself may be swapped out at runtime, see the
``become`` and ``unbecome`` operations. However, the initial behavior defined
during construction of the actor object is special in the sense that a restart
of the actor will reset its behavior to this initial one.
Mailbox
-------
An actor’s purpose is the processing of messages, and these messages were sent
to the actor from other actors (or from outside the actor system). The piece
which connects sender and receiver is the actor’s mailbox: each actor has
exactly one mailbox to which all senders enqueue their messages. Enqueuing
happens in the time-order of send operations, which means that messages sent
from different actors may not have a defined order at runtime due to the
apparent randomness of distributing actors across threads. Sending multiple
messages to the same target from the same actor, on the other hand, will
An actor’s purpose is the processing of messages, and these messages were sent
to the actor from other actors (or from outside the actor system). The piece
which connects sender and receiver is the actor’s mailbox: each actor has
exactly one mailbox to which all senders enqueue their messages. Enqueuing
happens in the time-order of send operations, which means that messages sent
from different actors may not have a defined order at runtime due to the
apparent randomness of distributing actors across threads. Sending multiple
messages to the same target from the same actor, on the other hand, will
enqueue them in the same order.
There are different mailbox implementations to choose from, the default being a
FIFO: the order of the messages processed by the actor matches the order in
which they were enqueued. This is usually a good default, but applications may
need to prioritize some messages over others. In this case, a priority mailbox
will enqueue not always at the end but at a position as given by the message
priority, which might even be at the front. While using such a queue, the order
of messages processed will naturally be defined by the queue’s algorithm and in
There are different mailbox implementations to choose from, the default being a
FIFO: the order of the messages processed by the actor matches the order in
which they were enqueued. This is usually a good default, but applications may
need to prioritize some messages over others. In this case, a priority mailbox
will enqueue not always at the end but at a position as given by the message
priority, which might even be at the front. While using such a queue, the order
of messages processed will naturally be defined by the queue’s algorithm and in
general not be FIFO.
An important feature in which Akka differs from some other actor model
implementations is that the current behavior must always handle the next
dequeued message, there is no scanning the mailbox for the next matching one.
Failure to handle a message will typically be treated as a failure, unless this
An important feature in which Akka differs from some other actor model
implementations is that the current behavior must always handle the next
dequeued message, there is no scanning the mailbox for the next matching one.
Failure to handle a message will typically be treated as a failure, unless this
behavior is overridden.
Children
--------
Each actor is potentially a supervisor: if it creates children for delegating
sub-tasks, it will automatically supervise them. The list of children is
maintained within the actor’s context and the actor has access to it.
Modifications to the list are done by creating (``context.actorOf(...)``) or
stopping (``context.stop(child)``) children and these actions are reflected
immediately. The actual creation and termination actions happen behind the
Each actor is potentially a supervisor: if it creates children for delegating
sub-tasks, it will automatically supervise them. The list of children is
maintained within the actor’s context and the actor has access to it.
Modifications to the list are done by creating (``context.actorOf(...)``) or
stopping (``context.stop(child)``) children and these actions are reflected
immediately. The actual creation and termination actions happen behind the
scenes in an asynchronous way, so they do not “block” their supervisor.
Fault Handling Strategy
-----------------------
Supervisor Strategy
-------------------
The final piece of an actor is its strategy for handling faults of its
children. To keep it simple and robust, this is declared outside of the actor’s
code and has no access to the actor’s state. Fault handling is then done
transparently by Akka, applying one of the strategies described in
:ref:`supervision` for each incoming failure. As this strategy is fundamental
to how an actor system is structured, it cannot be changed once an actor has
been created.
The final piece of an actor is its strategy for handling faults of its
children. Fault handling is then done transparently by Akka, applying one
of the strategies described in :ref:`supervision` for each incoming failure.
As this strategy is fundamental to how an actor system is structured, it
cannot be changed once an actor has been created.
Considering that there is only one such strategy for each actor, this means
that if different strategies apply to the various children of an actor, the
children should be grouped beneath intermediate supervisors with matching
strategies, preferring once more the structuring of actor systems according to
Considering that there is only one such strategy for each actor, this means
that if different strategies apply to the various children of an actor, the
children should be grouped beneath intermediate supervisors with matching
strategies, preferring once more the structuring of actor systems according to
the splitting of tasks into sub-tasks.
When an Actor Terminates

14
akka-docs/java/code/akka/docs/actor/FaultHandlingTestBase.java
View file

@ -6,8 +6,8 @@ package akka.docs.actor;
//#testkit
import akka.actor.ActorRef;
import akka.actor.ActorSystem;
import akka.actor.FaultHandlingStrategy;
import static akka.actor.FaultHandlingStrategy.*;
import akka.actor.SupervisorStrategy;
import static akka.actor.SupervisorStrategy.*;
import akka.actor.OneForOneStrategy;
import akka.actor.Props;
import akka.actor.Terminated;
@ -38,7 +38,7 @@ public class FaultHandlingTestBase {
static public class Supervisor extends UntypedActor {
//#strategy
private static FaultHandlingStrategy strategy = new OneForOneStrategy(new Function<Throwable, Action>() {
private static SupervisorStrategy strategy = new OneForOneStrategy(new Function<Throwable, Action>() {
@Override
public Action apply(Throwable t) {
if (t instanceof ArithmeticException) {
@ -54,7 +54,7 @@ public class FaultHandlingTestBase {
}, 10, 60000);
@Override
public FaultHandlingStrategy supervisorStrategy() {
public SupervisorStrategy supervisorStrategy() {
return strategy;
}
@ -75,7 +75,7 @@ public class FaultHandlingTestBase {
static public class Supervisor2 extends UntypedActor {
//#strategy2
private static FaultHandlingStrategy strategy = new OneForOneStrategy(new Function<Throwable, Action>() {
private static SupervisorStrategy strategy = new OneForOneStrategy(new Function<Throwable, Action>() {
@Override
public Action apply(Throwable t) {
if (t instanceof ArithmeticException) {
@ -91,7 +91,7 @@ public class FaultHandlingTestBase {
}, 10, 60000);
@Override
public FaultHandlingStrategy supervisorStrategy() {
public SupervisorStrategy supervisorStrategy() {
return strategy;
}
@ -147,7 +147,7 @@ public class FaultHandlingTestBase {
}
@Test
public void mustEmployFaultHandler() {
public void mustEmploySupervisorStrategy() {
// code here
//#testkit
EventFilter ex1 = (EventFilter) new ErrorFilter(ArithmeticException.class);

8
akka-docs/java/fault-tolerance.rst
View file

@ -1,7 +1,7 @@
.. _fault-tolerance-java:
Fault Handling Strategies (Java)
=================================
Fault Tolerance (Java)
======================
.. sidebar:: Contents
@ -12,8 +12,8 @@ children, and as such each actor defines fault handling supervisor strategy.
This strategy cannot be changed afterwards as it is an integral part of the
actor system’s structure.
Creating a Fault Handling Strategy
----------------------------------
Creating a Supervisor Strategy
------------------------------
For the sake of demonstration let us consider the following strategy:

11
akka-docs/java/typed-actors.rst
View file

@ -30,7 +30,7 @@ it's located in ``akka.actor.TypedActor``.
:include: typed-actor-extension-tools
.. warning::
Same as not exposing ``this`` of an Akka Actor, it's important not to expose ``this`` of a Typed Actor,
instead you should pass the external proxy reference, which is obtained from within your Typed Actor as
``TypedActor.self()``, this is your external identity, as the ``ActorRef`` is the external identity of
@ -127,7 +127,7 @@ Request-reply-with-future message send
.. includecode:: code/akka/docs/actor/TypedActorDocTestBase.java
:include: typed-actor-call-future
This call is asynchronous, and the Future returned can be used for asynchronous composition.
This call is asynchronous, and the Future returned can be used for asynchronous composition.
Stopping Typed Actors
---------------------
@ -153,6 +153,13 @@ you can create child Typed Actors by invoking ``typedActorOf(..)`` on that.
This also works for creating child Typed Actors in regular Akka Actors.
Supervisor Strategy
-------------------
By having your Typed Actor implementation class implement ``TypedActor.Supervisor``
you can define the strategy to use for supervising child actors, as described in
:ref:`supervision` and :ref:`fault-tolerance-java`.
Lifecycle callbacks
-------------------

1
akka-docs/java/untyped-actors.rst
View file

@ -129,6 +129,7 @@ In addition, it offers:
* :obj:`getSelf()` reference to the :class:`ActorRef` of the actor
* :obj:`getSender()` reference sender Actor of the last received message, typically used as described in :ref:`UntypedActor.Reply`
* :obj:`supervisorStrategy()` user overridable definition the strategy to use for supervising child actors
* :obj:`getContext()` exposes contextual information for the actor and the current message, such as:
* factory methods to create child actors (:meth:`actorOf`)

20
akka-docs/project/migration-guide-1.3.x-2.0.x.rst
View file

@ -403,7 +403,7 @@ v2.0::
context.parent
*Fault handling strategy*
*Supervisor Strategy*
v1.3::
@ -420,14 +420,18 @@ v1.3::
v2.0::
val strategy = OneForOneStrategy({
case _: ArithmeticException ⇒ Resume
case _: NullPointerException ⇒ Restart
case _: IllegalArgumentException ⇒ Stop
case _: Exception ⇒ Escalate
}: Decider, maxNrOfRetries = Some(10), withinTimeRange = Some(60000))
class MyActor extends Actor {
override val supervisorStrategy = OneForOneStrategy({
case _: ArithmeticException ⇒ Resume
case _: NullPointerException ⇒ Restart
case _: IllegalArgumentException ⇒ Stop
case _: Exception ⇒ Escalate
}: Decider, maxNrOfRetries = Some(10), withinTimeRange = Some(60000))
val supervisor = system.actorOf(Props[Supervisor].withFaultHandler(strategy), "supervisor")
def receive = {
case x =>
}
}
Documentation:

1
akka-docs/scala/actors.rst
View file

@ -154,6 +154,7 @@ In addition, it offers:
* :obj:`self` reference to the :class:`ActorRef` of the actor
* :obj:`sender` reference sender Actor of the last received message, typically used as described in :ref:`Actor.Reply`
* :obj:`supervisorStrategy` user overridable definition the strategy to use for supervising child actors
* :obj:`context` exposes contextual information for the actor and the current message, such as:
* factory methods to create child actors (:meth:`actorOf`)

4
akka-docs/scala/code/akka/docs/actor/FaultHandlingDocSpec.scala
View file

@ -19,7 +19,7 @@ object FaultHandlingDocSpec {
class Supervisor extends Actor {
//#strategy
import akka.actor.OneForOneStrategy
import akka.actor.FaultHandlingStrategy._
import akka.actor.SupervisorStrategy._
override val supervisorStrategy = OneForOneStrategy({
case _: ArithmeticException ⇒ Resume
@ -39,7 +39,7 @@ object FaultHandlingDocSpec {
class Supervisor2 extends Actor {
//#strategy2
import akka.actor.OneForOneStrategy
import akka.actor.FaultHandlingStrategy._
import akka.actor.SupervisorStrategy._
override val supervisorStrategy = OneForOneStrategy({
case _: ArithmeticException ⇒ Resume

8
akka-docs/scala/fault-tolerance.rst
View file

@ -1,7 +1,7 @@
.. _fault-tolerance-scala:
Fault Handling Strategies (Scala)
=================================
Fault Tolerance (Scala)
=======================
.. sidebar:: Contents
@ -12,8 +12,8 @@ children, and as such each actor defines fault handling supervisor strategy.
This strategy cannot be changed afterwards as it is an integral part of the
actor system’s structure.
Creating a Fault Handling Strategy
----------------------------------
Creating a Supervisor Strategy
------------------------------
For the sake of demonstration let us consider the following strategy:

11
akka-docs/scala/typed-actors.rst
View file

@ -30,7 +30,7 @@ it's located in ``akka.actor.TypedActor``.
:include: typed-actor-extension-tools
.. warning::
Same as not exposing ``this`` of an Akka Actor, it's important not to expose ``this`` of a Typed Actor,
instead you should pass the external proxy reference, which is obtained from within your Typed Actor as
``TypedActor.self``, this is your external identity, as the ``ActorRef`` is the external identity of
@ -127,7 +127,7 @@ Request-reply-with-future message send
.. includecode:: code/akka/docs/actor/TypedActorDocSpec.scala
:include: typed-actor-call-future
This call is asynchronous, and the Future returned can be used for asynchronous composition.
This call is asynchronous, and the Future returned can be used for asynchronous composition.
Stopping Typed Actors
---------------------
@ -153,6 +153,13 @@ you can create child Typed Actors by invoking ``typedActorOf(..)`` on that.
This also works for creating child Typed Actors in regular Akka Actors.
Supervisor Strategy
-------------------
By having your Typed Actor implementation class implement ``TypedActor.Supervisor``
you can define the strategy to use for supervising child actors, as described in
:ref:`supervision` and :ref:`fault-tolerance-scala`.
Lifecycle callbacks
-------------------