org.apache.flink.runtime.execution

Interface ExecutionListener

All Known Implementing Classes:

DefaultExecutionListener, EnvironmentListenerImpl, ExecutionGraph

public interface ExecutionListener

This interface must be implemented by classes which should be able to receive notifications about changes of a task's execution state.

Method Summary

Methods

Modifier and Type	Method and Description
void	executionStateChanged(JobID jobID, ExecutionVertexID vertexID, ExecutionState newExecutionState, String optionalMessage) Called when the execution state of the associated task has changed.
int	getPriority() Returns the priority of the execution listener object.
void	userThreadFinished(JobID jobID, ExecutionVertexID vertexID, Thread userThread) Called when a thread spawn by a user task has finished.
void	userThreadStarted(JobID jobID, ExecutionVertexID vertexID, Thread userThread) Called when the user task has started a new thread.

Method Detail

getPriority

int getPriority()

Returns the priority of the execution listener object. If multiple execution listener objects are registered for a given vertex, the priority determines in which order they will be called. Priorities are expressed as non-negative integer values. The lower the integer value, the higher the call priority.

Returns:

the priority of this execution listener

executionStateChanged

void executionStateChanged(JobID jobID,
                         ExecutionVertexID vertexID,
                         ExecutionState newExecutionState,
                         String optionalMessage)

Called when the execution state of the associated task has changed. It is important to point out that multiple execution listeners can be invoked as a reaction to a state change, according to their priority. As a result, the value of newExecutionState may be out-dated by the time a particular execution listener is called. To determine the most recent state of the respective task, it is recommended to store a reference on the execution that represents it and then call getExecutionState() on the vertex within this method.

Parameters:

jobID - the ID of the job the task belongs to

vertexID - the ID of the task whose state has changed

newExecutionState - the execution state the task has just switched to

optionalMessage - an optional message providing further information on the state change

userThreadStarted

void userThreadStarted(JobID jobID,
                     ExecutionVertexID vertexID,
                     Thread userThread)

Called when the user task has started a new thread.

Parameters:

jobID - the ID of the job the task belongs to

vertexID - the ID of the task that started of new thread

userThread - the user thread which has been started

userThreadFinished

void userThreadFinished(JobID jobID,
                      ExecutionVertexID vertexID,
                      Thread userThread)

Called when a thread spawn by a user task has finished.

Parameters:

jobID - the ID of the job the task belongs to

vertexID - the ID of the task whose thread has finished

userThread - the user thread which has finished