akka.routing
Class BalancingPool

java.lang.Object
  akka.routing.BalancingPool

All Implemented Interfaces:

Pool, RouterConfig, java.io.Serializable, scala.Equals, scala.Product

public final class BalancingPool
extends java.lang.Object
implements Pool, scala.Product, scala.Serializable

A router pool that will try to redistribute work from busy routees to idle routees. All routees share the same mailbox.

Although the technique used in this implementation is commonly known as "work stealing", the actual implementation is probably best described as "work donating" because the actor of which work is being stolen takes the initiative.

The configuration parameter trumps the constructor arguments. This means that if you provide nrOfInstances during instantiation they will be ignored if the router is defined in the configuration file for the actor being used.

Supervision Setup

Any routees that are created by a router will be created as the router's children. The router is therefore also the children's supervisor.

The supervision strategy of the router actor can be configured with withSupervisorStrategy(akka.actor.SupervisorStrategy). If no strategy is provided, routers default to a strategy of “always escalate”. This means that errors are passed up to the router's supervisor for handling.

The router's supervisor will treat the error as an error with the router itself. Therefore a directive to stop or restart will cause the router itself to stop or restart. The router, in turn, will cause its children to stop and restart.

param: nrOfInstances initial number of routees in the pool

param: supervisorStrategy strategy for supervising the routees, see 'Supervision Setup'

param: routerDispatcher dispatcher to use for the router head actor, which handles supervision, death watch and router management messages

See Also:

Serialized Form

Constructor Summary

BalancingPool(com.typesafe.config.Config config)

BalancingPool(int nrOfInstances, SupervisorStrategy supervisorStrategy, java.lang.String routerDispatcher)

Method Summary

Router	createRouter(ActorSystem system) Create the actual router, responsible for routing messages to routees.
Routee	newRoutee(Props routeeProps, ActorContext context) INTERNAL API
int	nrOfInstances() Initial number of routee instances
scala.Option<Resizer>	resizer() Resizer cannot be used together with BalancingPool
java.lang.String	routerDispatcher() Dispatcher ID to use for running the &ldquo;head&rdquo; actor, which handles supervision, death watch and router management messages
SupervisorStrategy	supervisorStrategy() SupervisorStrategy for the head actor, i.e.
BalancingPool	withDispatcher(java.lang.String dispatcherId) Setting the dispatcher to be used for the router head actor, which handles supervision, death watch and router management messages.
RouterConfig	withFallback(RouterConfig other) Uses the supervisor strategy of the given Routerconfig if this RouterConfig doesn't have one.
BalancingPool	withSupervisorStrategy(SupervisorStrategy strategy) Setting the supervisor strategy to be used for the &ldquo;head&rdquo; Router actor.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface akka.routing.Pool

createRouterActor, enrichWithPoolDispatcher, props, stopRouterWhenAllRouteesRemoved, usePoolDispatcher

Methods inherited from interface akka.routing.RouterConfig

isManagementMessage, routingLogicController, verifyConfig

Methods inherited from interface scala.Product

productArity, productElement, productIterator, productPrefix

Methods inherited from interface scala.Equals

canEqual, equals

Constructor Detail

BalancingPool

public BalancingPool(int nrOfInstances,
                     SupervisorStrategy supervisorStrategy,
                     java.lang.String routerDispatcher)

BalancingPool

public BalancingPool(com.typesafe.config.Config config)

Method Detail

nrOfInstances

public int nrOfInstances()

Description copied from interface: Pool

Initial number of routee instances

Specified by:

nrOfInstances in interface Pool

Returns:

(undocumented)

supervisorStrategy

public SupervisorStrategy supervisorStrategy()

Description copied from interface: Pool

SupervisorStrategy for the head actor, i.e. for supervising the routees of the pool.

Specified by:

supervisorStrategy in interface Pool

Returns:

(undocumented)

routerDispatcher

public java.lang.String routerDispatcher()

Description copied from interface: RouterConfig

Dispatcher ID to use for running the “head” actor, which handles supervision, death watch and router management messages

Specified by:

routerDispatcher in interface RouterConfig

Returns:

(undocumented)

createRouter

public Router createRouter(ActorSystem system)

Description copied from interface: RouterConfig

Create the actual router, responsible for routing messages to routees.

Specified by:

createRouter in interface RouterConfig

Parameters:

system - the ActorSystem this router belongs to

Returns:

(undocumented)

withSupervisorStrategy

public BalancingPool withSupervisorStrategy(SupervisorStrategy strategy)

Setting the supervisor strategy to be used for the “head” Router actor.

Parameters:

strategy - (undocumented)

Returns:

(undocumented)

withDispatcher

public BalancingPool withDispatcher(java.lang.String dispatcherId)

Setting the dispatcher to be used for the router head actor, which handles supervision, death watch and router management messages.

Parameters:

dispatcherId - (undocumented)

Returns:

(undocumented)

newRoutee

public Routee newRoutee(Props routeeProps,
                        ActorContext context)

INTERNAL API

Specified by:

newRoutee in interface Pool

Parameters:

routeeProps - (undocumented)

context - (undocumented)

Returns:

(undocumented)

withFallback

public RouterConfig withFallback(RouterConfig other)

Uses the supervisor strategy of the given Routerconfig if this RouterConfig doesn't have one.

Specified by:

withFallback in interface RouterConfig

Parameters:

other - (undocumented)

Returns:

(undocumented)

resizer

public scala.Option<Resizer> resizer()

Resizer cannot be used together with BalancingPool

Specified by:

resizer in interface Pool

Returns:

(undocumented)