akka.routing
Class RoundRobinPool

java.lang.Object
  extended by akka.routing.RoundRobinPool
All Implemented Interfaces:
Pool, PoolOverrideUnsetConfig<RoundRobinPool>, RouterConfig, java.io.Serializable, scala.Equals, scala.Product

public final class RoundRobinPool
extends java.lang.Object
implements Pool, PoolOverrideUnsetConfig<RoundRobinPool>, scala.Product, scala.Serializable

A router pool that uses round-robin to select a routee. For concurrent calls, round robin is just a best effort.

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 &ldquo;always escalate&rdquo;. 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: resizer optional resizer that dynamically adjust the pool size

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
RoundRobinPool(com.typesafe.config.Config config)
           
RoundRobinPool(int nrOfInstances, scala.Option<Resizer> resizer, SupervisorStrategy supervisorStrategy, java.lang.String routerDispatcher, boolean usePoolDispatcher)
           
 
Method Summary
 Router createRouter(ActorSystem system)
          Create the actual router, responsible for routing messages to routees.
 int nrOfInstances()
          Initial number of routee instances
 scala.Option<Resizer> resizer()
          Pool with dynamically resizable number of routees return the Resizer to use.
 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.
 boolean usePoolDispatcher()
          Use a dedicated dispatcher for the routees of the pool.
 RoundRobinPool 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 resizer and/or the supervisor strategy of the given Routerconfig if this RouterConfig doesn't have one, i.e.
 RoundRobinPool withResizer(Resizer resizer)
          Setting the resizer to be used.
 RoundRobinPool 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.PoolOverrideUnsetConfig
overrideUnsetConfig
 
Methods inherited from interface akka.routing.Pool
createRouterActor, enrichWithPoolDispatcher, newRoutee, props, stopRouterWhenAllRouteesRemoved
 
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

RoundRobinPool

public RoundRobinPool(int nrOfInstances,
                      scala.Option<Resizer> resizer,
                      SupervisorStrategy supervisorStrategy,
                      java.lang.String routerDispatcher,
                      boolean usePoolDispatcher)

RoundRobinPool

public RoundRobinPool(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)

resizer

public scala.Option<Resizer> resizer()
Description copied from interface: Pool
Pool with dynamically resizable number of routees return the Resizer to use. The resizer is invoked once when the router is created, before any messages can be sent to it. Resize is also triggered when messages are sent to the routees, and the resizer is invoked asynchronously, i.e. not necessarily before the message has been sent.

Specified by:
resizer 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 &ldquo;head&rdquo; actor, which handles supervision, death watch and router management messages

Specified by:
routerDispatcher in interface RouterConfig
Returns:
(undocumented)

usePoolDispatcher

public boolean usePoolDispatcher()
Description copied from interface: Pool
Use a dedicated dispatcher for the routees of the pool. The dispatcher is defined in 'pool-dispatcher' configuration property in the deployment section of the router.

Specified by:
usePoolDispatcher in interface Pool
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 RoundRobinPool withSupervisorStrategy(SupervisorStrategy strategy)
Setting the supervisor strategy to be used for the &ldquo;head&rdquo; Router actor.

Specified by:
withSupervisorStrategy in interface PoolOverrideUnsetConfig<RoundRobinPool>
Parameters:
strategy - (undocumented)
Returns:
(undocumented)

withResizer

public RoundRobinPool withResizer(Resizer resizer)
Setting the resizer to be used.

Specified by:
withResizer in interface PoolOverrideUnsetConfig<RoundRobinPool>
Parameters:
resizer - (undocumented)
Returns:
(undocumented)

withDispatcher

public RoundRobinPool 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)

withFallback

public RouterConfig withFallback(RouterConfig other)
Uses the resizer and/or the supervisor strategy of the given Routerconfig if this RouterConfig doesn't have one, i.e. the resizer defined in code is used if resizer was not defined in config.

Specified by:
withFallback in interface RouterConfig
Parameters:
other - (undocumented)
Returns:
(undocumented)