org.apache.ignite.events

Class TaskEvent

java.lang.Object

org.apache.ignite.events.EventAdapter

org.apache.ignite.events.TaskEvent

All Implemented Interfaces:

Serializable, Comparable<Event>, Event

Direct Known Subclasses:

TaskWithAttributesEvent

public class TaskEvent
extends EventAdapter

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

User can also wait for events using method IgniteEvents.waitForLocal(org.apache.ignite.lang.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_TASK_FAILED, EventType.EVT_TASK_FINISHED, EventType.EVT_TASK_REDUCED, EventType.EVT_TASK_STARTED, EventType.EVT_TASK_SESSION_ATTR_SET, EventType.EVT_TASK_TIMEDOUT, EventType.EVTS_TASK_EXECUTION, Serialized Form

Constructor Summary

Constructors

Constructor and Description
TaskEvent(ClusterNode node, String msg, int type, IgniteUuid sesId, String taskName, String taskClsName, boolean internal, @Nullable UUID subjId) Creates task event with given parameters.

Method Summary

Modifier and Type	Method and Description
boolean	internal() Returns true if task is created by Ignite and is used for system needs.
String	shortDisplay() Gets a shortened version of toString() result.
@Nullable UUID	subjectId() Gets security subject ID initiated this task event, if available.
String	taskClassName() Gets name of task class that triggered this event.
String	taskName() Gets name of the task that triggered the event.
IgniteUuid	taskSessionId() Gets session ID of the task that triggered the event.
String	toString()

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

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

Methods inherited from class java.lang.Object

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

Constructor Detail

TaskEvent

public TaskEvent(ClusterNode node,
                 String msg,
                 int type,
                 IgniteUuid sesId,
                 String taskName,
                 String taskClsName,
                 boolean internal,
                 @Nullable
                 @Nullable UUID subjId)

Creates task event with given parameters.

Parameters:

node - Node.

msg - Optional message.

type - Event type.

sesId - Task session ID.

taskName - Task name.

subjId - Subject ID.

Method Detail

shortDisplay

public String shortDisplay()

Gets a shortened version of toString() result. Suitable for humans to read.

Specified by:

shortDisplay in interface Event

Overrides:

shortDisplay in class EventAdapter

Returns:

Shortened version of toString() result.

taskName

public String taskName()

Gets name of the task that triggered the event.

Returns:

Name of the task that triggered the event.

taskClassName

public String taskClassName()

Gets name of task class that triggered this event.

Returns:

Name of task class that triggered the event.

taskSessionId

public IgniteUuid taskSessionId()

Gets session ID of the task that triggered the event.

Returns:

Session ID of the task that triggered the event.

internal

public boolean internal()

Returns true if task is created by Ignite and is used for system needs.

Returns:

True if task is created by Ignite and is used for system needs.

subjectId

@Nullable
public @Nullable UUID subjectId()

Gets security subject ID initiated this task event, if available. This property is not available for GridEventType#EVT_TASK_SESSION_ATTR_SET task event.

Subject ID will be set either to node ID or client ID initiated task execution.

Returns:

Subject ID.

toString

public String toString()

Overrides:

toString in class EventAdapter