org.apache.ignite.events

Class ClusterStateChangeStartedEvent

java.lang.Object

org.apache.ignite.events.EventAdapter

org.apache.ignite.events.ClusterStateChangeStartedEvent

All Implemented Interfaces:

Serializable, Comparable<Event>, Event

public class ClusterStateChangeStartedEvent
extends EventAdapter

Cluster state change started event.

Grid events are used for notification about what happens within the grid. Note that by design Ignite keeps all events generated on the local node locally and it provides APIs for performing a distributed queries across multiple nodes:

• IgniteEvents.remoteQuery(IgnitePredicate, long, int...) - asynchronously querying events occurred on the nodes specified, including remote nodes.
• IgniteEvents.localQuery(IgnitePredicate, int...) - querying only local events stored on this local node.
• IgniteEvents.localListen(IgnitePredicate, int...) - listening to local grid events (events from remote nodes not included).

User can also wait for events using method IgniteEvents.waitForLocal(IgnitePredicate, int...).

Events and Performance

Note that by default all events in Ignite are enabled and therefore generated and stored by whatever event storage SPI is configured. Ignite can and often does generate thousands events per seconds under the load and therefore it creates a significant additional load on the system. If these events are not needed by the application this load is unnecessary and leads to significant performance degradation.

It is highly recommended to enable only those events that your application logic requires by using IgniteConfiguration.getIncludeEventTypes() method in Ignite configuration. Note that certain events are required for Ignite's internal operations and such events will still be generated but not stored by event storage SPI if they are disabled in Ignite configuration.

See Also:

EventType.EVT_CLUSTER_STATE_CHANGE_STARTED, Serialized Form

Constructor Summary

Constructors

Constructor and Description
ClusterStateChangeStartedEvent(ClusterState prevState, ClusterState state, ClusterNode node, String msg)

Method Summary

Modifier and Type	Method and Description
ClusterState	previousState()
ClusterState	state()

Methods inherited from class org.apache.ignite.events.EventAdapter

compareTo, equals, hashCode, id, localOrder, message, message, name, node, node, shortDisplay, timestamp, toString, type, type

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ClusterStateChangeStartedEvent

public ClusterStateChangeStartedEvent(ClusterState prevState,
                                      ClusterState state,
                                      ClusterNode node,
                                      String msg)

Parameters:

prevState - Previous cluster state.

state - New cluster state.

node - Node.

msg - Optional event message.

Method Detail

previousState

public ClusterState previousState()

Returns:

Previous cluster state.

state

public ClusterState state()

Returns:

New cluster state.