org.apache.cassandra.gms

Interface IEndpointStateChangeSubscriber

All Known Implementing Classes:

ActiveRepairService, LoadBroadcaster, ReconnectableSnitchHelper, RepairSession, StorageService, StreamSession

public interface IEndpointStateChangeSubscriber

This is called by an instance of the IEndpointStateChangePublisher to notify interested parties about changes in the the state associated with any endpoint. For instance if node A figures there is a changes in state for an endpoint B it notifies all interested parties of this change. It is upto to the registered instance to decide what he does with this change. Not all modules maybe interested in all state changes.

Method Summary

Modifier and Type	Method and Description
default void	beforeChange(InetAddressAndPort endpoint, EndpointState currentState, ApplicationState newStateKey, VersionedValue newValue)
default void	onAlive(InetAddressAndPort endpoint, EndpointState state)
default void	onChange(InetAddressAndPort endpoint, ApplicationState state, VersionedValue value)
default void	onDead(InetAddressAndPort endpoint, EndpointState state)
default void	onJoin(InetAddressAndPort endpoint, EndpointState epState) Use to inform interested parties about the change in the state for specified endpoint
default void	onRemove(InetAddressAndPort endpoint)
default void	onRestart(InetAddressAndPort endpoint, EndpointState state) Called whenever a node is restarted.

Method Detail

onJoin

default void onJoin(InetAddressAndPort endpoint,
                    EndpointState epState)

Use to inform interested parties about the change in the state for specified endpoint

Parameters:

endpoint - endpoint for which the state change occurred.

epState - state that actually changed for the above endpoint.

beforeChange

default void beforeChange(InetAddressAndPort endpoint,
                          EndpointState currentState,
                          ApplicationState newStateKey,
                          VersionedValue newValue)

onChange

default void onChange(InetAddressAndPort endpoint,
                      ApplicationState state,
                      VersionedValue value)

onAlive

default void onAlive(InetAddressAndPort endpoint,
                     EndpointState state)

onDead

default void onDead(InetAddressAndPort endpoint,
                    EndpointState state)

onRemove

default void onRemove(InetAddressAndPort endpoint)

onRestart

default void onRestart(InetAddressAndPort endpoint,
                       EndpointState state)

Called whenever a node is restarted. Note that there is no guarantee when that happens that the node was previously marked down. It will have only if state.isAlive() == false as state is from before the restarted node is marked up.