public interface ClusterSingletonServiceProvider extends AutoCloseable
ClusterSingletonServiceProvider provides a functionality to register and group services
ClusterSingletonService by service group identifier. Services could be Applications or RPCs.
Provider provides a functionality which allows to have only one fully instantiated service instance
in a cluster at one time and service group means to have all service instances for the same group
situated on same Cluster Node. This is realized via a double candidate approach where a service
group instance maintains a candidate registration for ownership of the service group entity in the
cluster and also a registration that acts as a guard to ensure a service group instance has fully
closed prior to relinquishing service group ownership. To achieve ownership of the service group,
a service group candidate must hold ownership of both these entities.| Modifier and Type | Method and Description |
|---|---|
ClusterSingletonServiceRegistration |
registerClusterSingletonService(ClusterSingletonService service)
Method registers
ClusterSingletonService to Provider. |
closeClusterSingletonServiceRegistration registerClusterSingletonService(ClusterSingletonService service)
ClusterSingletonService to Provider.
Method returns RuntimeException for unexpected state, so be careful with implementation.
Note: RuntimeException is implemented as a notification about some problems with registration and client
has to implement some strategy for handling this issue.
TODO: RuntimeException is not a transparent contract for handling unexpected state and it needs to be
replaced with a specific documented Exception or it needs to add another contract definition for a client
notification about the unexpected state reason in ClusterSingletonService.
RuntimeException implementation is a hotfix for an unwanted API contract changes in boron release only.service - ClusterSingletonService instanceAutoCloseable registrationCopyright © 2019 OpenDaylight. All rights reserved.