org.apache.hadoop.mapreduce

Class TaskCompletionEvent

java.lang.Object

org.apache.hadoop.mapreduce.TaskCompletionEvent

All Implemented Interfaces:

Writable

Direct Known Subclasses:

TaskCompletionEvent

@InterfaceAudience.Public
@InterfaceStability.Evolving
public class TaskCompletionEvent
extends Object
implements Writable

This is used to track task completion events on job tracker.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TaskCompletionEvent.Status

Field Summary

Fields

Modifier and Type	Field and Description
static TaskCompletionEvent[]	EMPTY_ARRAY

Constructor Summary

Constructors

Constructor and Description
TaskCompletionEvent() Default constructor for Writable.
TaskCompletionEvent(int eventId, TaskAttemptID taskId, int idWithinJob, boolean isMap, TaskCompletionEvent.Status status, String taskTrackerHttp) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object o)
int	getEventId() Returns event Id.
TaskCompletionEvent.Status	getStatus() Returns enum Status.SUCESS or Status.FAILURE.
TaskAttemptID	getTaskAttemptId() Returns task id.
int	getTaskRunTime() Returns time (in millisec) the task took to complete.
String	getTaskTrackerHttp() http location of the tasktracker where this task ran.
int	hashCode()
int	idWithinJob()
boolean	isMapTask()
void	readFields(DataInput in) Deserialize the fields of this object from in.
protected void	setEventId(int eventId) set event Id.
protected void	setTaskAttemptId(TaskAttemptID taskId) Sets task id.
protected void	setTaskRunTime(int taskCompletionTime) Set the task completion time
protected void	setTaskStatus(TaskCompletionEvent.Status status) Set task status.
protected void	setTaskTrackerHttp(String taskTrackerHttp) Set task tracker http location.
String	toString()
void	write(DataOutput out) Serialize the fields of this object to out.

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_ARRAY

public static final TaskCompletionEvent[] EMPTY_ARRAY

Constructor Detail

TaskCompletionEvent

public TaskCompletionEvent()

Default constructor for Writable.

TaskCompletionEvent

public TaskCompletionEvent(int eventId,
                   TaskAttemptID taskId,
                   int idWithinJob,
                   boolean isMap,
                   TaskCompletionEvent.Status status,
                   String taskTrackerHttp)

Constructor. eventId should be created externally and incremented per event for each job.

Parameters:

eventId - event id, event id should be unique and assigned in incrementally, starting from 0.

taskId - task id

status - task's status

taskTrackerHttp - task tracker's host:port for http.

Method Detail

getEventId

public int getEventId()

Returns event Id.

Returns:

event id

getTaskAttemptId

public TaskAttemptID getTaskAttemptId()

Returns task id.

Returns:

task id

getStatus

public TaskCompletionEvent.Status getStatus()

Returns enum Status.SUCESS or Status.FAILURE.

Returns:

task tracker status

getTaskTrackerHttp

public String getTaskTrackerHttp()

http location of the tasktracker where this task ran.

Returns:

http location of tasktracker user logs

getTaskRunTime

public int getTaskRunTime()

Returns time (in millisec) the task took to complete.

setTaskRunTime

protected void setTaskRunTime(int taskCompletionTime)

Set the task completion time

Parameters:

taskCompletionTime - time (in millisec) the task took to complete

setEventId

protected void setEventId(int eventId)

set event Id. should be assigned incrementally starting from 0.

Parameters:

eventId -

setTaskAttemptId

protected void setTaskAttemptId(TaskAttemptID taskId)

Sets task id.

Parameters:

taskId -

setTaskStatus

protected void setTaskStatus(TaskCompletionEvent.Status status)

Set task status.

Parameters:

status -

setTaskTrackerHttp

protected void setTaskTrackerHttp(String taskTrackerHttp)

Set task tracker http location.

Parameters:

taskTrackerHttp -

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

isMapTask

public boolean isMapTask()

idWithinJob

public int idWithinJob()

write

public void write(DataOutput out)
           throws IOException

Description copied from interface: Writable

Serialize the fields of this object to out.

Specified by:

write in interface Writable

Parameters:

out - DataOuput to serialize this object into.

Throws:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

Description copied from interface: Writable

Deserialize the fields of this object from in.

For efficiency, implementations should attempt to re-use storage in the existing object where possible.

Specified by:

readFields in interface Writable

Parameters:

in - DataInput to deseriablize this object from.

Throws:

IOException