Package org.elasticsearch.cluster

Class ClusterStateUpdateTask

java.lang.Object

org.elasticsearch.cluster.ClusterStateUpdateTask

All Implemented Interfaces:

ClusterStateTaskConfig, ClusterStateTaskExecutor<ClusterStateUpdateTask>, ClusterStateTaskListener

Direct Known Subclasses:

AckedClusterStateUpdateTask, SystemIndexMetadataUpgradeService.SystemIndexMetadataUpdateTask

public abstract class ClusterStateUpdateTask
extends Object
implements ClusterStateTaskConfig, ClusterStateTaskExecutor<ClusterStateUpdateTask>, ClusterStateTaskListener

A task that can update the cluster state.

Nested Class Summary

Nested classes/interfaces inherited from interface org.elasticsearch.cluster.ClusterStateTaskConfig

ClusterStateTaskConfig.Basic

Nested classes/interfaces inherited from interface org.elasticsearch.cluster.ClusterStateTaskExecutor

ClusterStateTaskExecutor.ClusterTasksResult<T>, ClusterStateTaskExecutor.TaskResult

Constructor Summary

Constructors

Constructor	Description
ClusterStateUpdateTask()
ClusterStateUpdateTask(Priority priority)
ClusterStateUpdateTask(Priority priority, org.elasticsearch.core.TimeValue timeout)
ClusterStateUpdateTask(org.elasticsearch.core.TimeValue timeout)

Method Summary

Modifier and Type	Method	Description
void	clusterStatePublished(ClusterChangedEvent clusterChangedEvent)	Callback invoked after new cluster state is published.
String	describeTasks(List<ClusterStateUpdateTask> tasks)	Builds a concise description of a list of tasks (to be used in logging etc.).
abstract ClusterState	execute(ClusterState currentState)	Update the cluster state based on the current state.
ClusterStateTaskExecutor.ClusterTasksResult<ClusterStateUpdateTask>	execute(ClusterState currentState, List<ClusterStateUpdateTask> tasks)	Update the cluster state based on the current state and the given tasks.
abstract void	onFailure(String source, Exception e)	A callback for when task execution fails.
Priority	priority()	The Priority for this cluster state update task configuration.
boolean	runOnlyOnMaster()	Marked as final as cluster state update tasks should only run on master.
org.elasticsearch.core.TimeValue	timeout()	If the cluster state update task wasn't processed by the provided timeout, call ClusterStateTaskListener.onFailure(String, Exception).

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.elasticsearch.cluster.ClusterStateTaskListener

clusterStateProcessed, onNoLongerMaster

Constructor Details

ClusterStateUpdateTask

public ClusterStateUpdateTask()

ClusterStateUpdateTask

public ClusterStateUpdateTask(Priority priority)

ClusterStateUpdateTask

public ClusterStateUpdateTask(org.elasticsearch.core.TimeValue timeout)

ClusterStateUpdateTask

public ClusterStateUpdateTask(Priority priority,
 org.elasticsearch.core.TimeValue timeout)

Method Details

execute

public final ClusterStateTaskExecutor.ClusterTasksResult<ClusterStateUpdateTask> execute(ClusterState currentState,
 List<ClusterStateUpdateTask> tasks)
                                                                                  throws Exception

Description copied from interface: ClusterStateTaskExecutor

Update the cluster state based on the current state and the given tasks. Return the *same instance* if no state should be changed.

Specified by:

execute in interface ClusterStateTaskExecutor<ClusterStateUpdateTask>

Throws:

Exception

describeTasks

public String describeTasks(List<ClusterStateUpdateTask> tasks)

Description copied from interface: ClusterStateTaskExecutor

Builds a concise description of a list of tasks (to be used in logging etc.). Note that the tasks given are not necessarily the same as those that will be passed to ClusterStateTaskExecutor.execute(ClusterState, List). but are guaranteed to be a subset of them. This method can be called multiple times with different lists before execution. This allows groupd task description but the submitting source.

Specified by:

describeTasks in interface ClusterStateTaskExecutor<ClusterStateUpdateTask>

execute

public abstract ClusterState execute(ClusterState currentState)
                              throws Exception

Update the cluster state based on the current state. Return the *same instance* if no state should be changed.

Throws:

Exception

onFailure

public abstract void onFailure(String source,
 Exception e)

A callback for when task execution fails. Implementations of this callback should not throw exceptions: an exception thrown here is logged by the master service at ERROR level and otherwise ignored. If log-and-ignore is the right behaviour then implementations should do so themselves, typically using a more specific logger and at a less dramatic log level.

Specified by:

onFailure in interface ClusterStateTaskListener

clusterStatePublished

public final void clusterStatePublished(ClusterChangedEvent clusterChangedEvent)

Description copied from interface: ClusterStateTaskExecutor

Callback invoked after new cluster state is published. Note that this method is not invoked if the cluster state was not updated. Note that this method will be executed using system context.

Specified by:

clusterStatePublished in interface ClusterStateTaskExecutor<ClusterStateUpdateTask>

Parameters:

clusterChangedEvent - the change event for this cluster state change, containing both old and new states

timeout

@Nullable
public final org.elasticsearch.core.TimeValue timeout()

If the cluster state update task wasn't processed by the provided timeout, call ClusterStateTaskListener.onFailure(String, Exception). May return null to indicate no timeout is needed (default).

Specified by:

timeout in interface ClusterStateTaskConfig

Returns:

the timeout, or null if one is not set

priority

public final Priority priority()

Description copied from interface: ClusterStateTaskConfig

The Priority for this cluster state update task configuration.

Specified by:

priority in interface ClusterStateTaskConfig

Returns:

the priority

runOnlyOnMaster

public final boolean runOnlyOnMaster()

Marked as final as cluster state update tasks should only run on master. For local requests, use LocalClusterUpdateTask instead.

Specified by:

runOnlyOnMaster in interface ClusterStateTaskExecutor<ClusterStateUpdateTask>