org.apache.ignite.events

Class ClusterStateChangeEvent

java.lang.Object

org.apache.ignite.events.EventAdapter

org.apache.ignite.events.ClusterStateChangeEvent

All Implemented Interfaces:

Serializable, Comparable<Event>, Event

public class ClusterStateChangeEvent
extends EventAdapter

Cluster state change 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_CHANGED, Serialized Form

Constructor Summary

Constructors

Constructor and Description
ClusterStateChangeEvent(ClusterState prevState, ClusterState state, @Nullable Collection<BaselineNode> baselineNodes, ClusterNode node, String msg)

Method Summary

Modifier and Type	Method and Description
@Nullable Collection<BaselineNode>	baselineNodes() Gets baseline nodes.
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

ClusterStateChangeEvent

public ClusterStateChangeEvent(ClusterState prevState,
                               ClusterState state,
                               @Nullable
                               @Nullable Collection<BaselineNode> baselineNodes,
                               ClusterNode node,
                               String msg)

Parameters:

prevState - Previous cluster state.

state - Current cluster state.

baselineNodes - Collection of baseline nodes. (Optional for in-memory case)

node - Node.

msg - Optional event message.

Method Detail

previousState

public ClusterState previousState()

Returns:

Previous cluster state.

state

public ClusterState state()

Returns:

Current cluster state.

baselineNodes

@Nullable
public @Nullable Collection<BaselineNode> baselineNodes()

Gets baseline nodes.

Returns:

Baseline nodes.