akka.cluster

Class DowningProvider

java.lang.Object

akka.cluster.DowningProvider

Direct Known Subclasses:

AutoDowning, NoDowning

public abstract class DowningProvider
extends java.lang.Object

API for plugins that will handle downing of cluster nodes. Concrete plugins must subclass and have a public one argument constructor accepting an ActorSystem.

Constructor Summary

Constructors

Constructor and Description
DowningProvider()

Method Summary

Modifier and Type	Method and Description
abstract scala.Option<Props>	downingActorProps() If a props is returned it is created as a child of the core cluster daemon on cluster startup.
abstract scala.concurrent.duration.FiniteDuration	downRemovalMargin() Time margin after which shards or singletons that belonged to a downed/removed partition are created in surviving partition.
static DowningProvider	load(java.lang.String fqcn, ActorSystem system)

Methods inherited from class java.lang.Object

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

Constructor Detail

DowningProvider

public DowningProvider()

Method Detail

load

public static DowningProvider load(java.lang.String fqcn,
                                   ActorSystem system)

Parameters:

fqcn - Fully qualified class name of the implementation to be loaded.

system - Actor system used to load the implemntation

Returns:

the provider or throws a ConfigurationException if loading it fails

downRemovalMargin

public abstract scala.concurrent.duration.FiniteDuration downRemovalMargin()

Time margin after which shards or singletons that belonged to a downed/removed partition are created in surviving partition. The purpose of this margin is that in case of a network partition the persistent actors in the non-surviving partitions must be stopped before corresponding persistent actors are started somewhere else. This is useful if you implement downing strategies that handle network partitions, e.g. by keeping the larger side of the partition and shutting down the smaller side.

Returns:

(undocumented)

downingActorProps

public abstract scala.Option<Props> downingActorProps()

If a props is returned it is created as a child of the core cluster daemon on cluster startup. It should then handle downing using the regular Cluster APIs. The actor will run on the same dispatcher as the cluster actor if dispatcher not configured.

May throw an exception which will then immediately lead to Cluster stopping, as the downing provider is vital to a working cluster.

Returns:

(undocumented)