org.apache.hadoop.mapreduce.jobhistory

Class JobHistoryEventHandler

java.lang.Object

org.apache.hadoop.service.AbstractService

org.apache.hadoop.mapreduce.jobhistory.JobHistoryEventHandler

All Implemented Interfaces:

Closeable, AutoCloseable, Service, EventHandler<JobHistoryEvent>

public class JobHistoryEventHandler
extends AbstractService
implements EventHandler<JobHistoryEvent>

The job history events get routed to this class. This class writes the Job history events to the DFS directly into a staging dir and then moved to a done-dir. JobHistory implementation is in this package to access package private classes.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	JobHistoryEventHandler.MetaInfo

Nested classes/interfaces inherited from interface org.apache.hadoop.service.Service

Service.STATE

Field Summary

Fields

Modifier and Type	Field and Description
protected Thread	eventHandlingThread
protected BlockingQueue<JobHistoryEvent>	eventQueue
protected static Map<JobId,JobHistoryEventHandler.MetaInfo>	fileMap
protected boolean	forceJobCompletion

Constructor Summary

Constructors

Constructor and Description
JobHistoryEventHandler(AppContext context, int startCount)

Method Summary

Methods

Modifier and Type	Method and Description
protected void	closeEventWriter(JobId jobId)
void	closeWriter(JobId id) Close the event writer for this id
protected org.apache.hadoop.mapreduce.jobhistory.EventWriter	createEventWriter(Path historyFilePath)
void	handle(JobHistoryEvent event)
protected void	handleEvent(JobHistoryEvent event)
protected void	processDoneFiles(JobId jobId)
void	processEventForJobSummary(HistoryEvent event, JobSummary summary, JobId jobId)
protected void	serviceInit(Configuration conf) All initialization code needed by a service.
protected void	serviceStart() Actions called during the INITED to STARTED transition.
protected void	serviceStop() Actions called during the transition to the STOPPED state.
void	setForcejobCompletion(boolean forceJobCompletion)
protected void	setupEventWriter(JobId jobId) Create an event writer for the Job represented by the jobID.

Methods inherited from class org.apache.hadoop.service.AbstractService

close, getBlockers, getConfig, getFailureCause, getFailureState, getLifecycleHistory, getName, getServiceState, getStartTime, init, isInState, noteFailure, putBlocker, registerGlobalListener, registerServiceListener, removeBlocker, setConfig, start, stop, toString, unregisterGlobalListener, unregisterServiceListener, waitForServiceToStop

Methods inherited from class java.lang.Object

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

Field Detail

eventQueue

protected BlockingQueue<JobHistoryEvent> eventQueue

eventHandlingThread

protected Thread eventHandlingThread

fileMap

protected static final Map<JobId,JobHistoryEventHandler.MetaInfo> fileMap

forceJobCompletion

protected volatile boolean forceJobCompletion

Constructor Detail

JobHistoryEventHandler

public JobHistoryEventHandler(AppContext context,
                      int startCount)

Method Detail

serviceInit

protected void serviceInit(Configuration conf)
                    throws Exception

Description copied from class: AbstractService

All initialization code needed by a service. This method will only ever be called once during the lifecycle of a specific service instance. Implementations do not need to be synchronized as the logic in AbstractService.init(Configuration) prevents re-entrancy. The base implementation checks to see if the subclass has created a new configuration instance, and if so, updates the base class value

Overrides:

serviceInit in class AbstractService

Parameters:

conf - configuration

Throws:

Exception - on a failure -these will be caught, possibly wrapped, and wil; trigger a service stop

serviceStart

protected void serviceStart()
                     throws Exception

Description copied from class: AbstractService

Actions called during the INITED to STARTED transition. This method will only ever be called once during the lifecycle of a specific service instance. Implementations do not need to be synchronized as the logic in AbstractService.start() prevents re-entrancy.

Overrides:

serviceStart in class AbstractService

Throws:

Exception - if needed -these will be caught, wrapped, and trigger a service stop

serviceStop

protected void serviceStop()
                    throws Exception

Description copied from class: AbstractService

Actions called during the transition to the STOPPED state. This method will only ever be called once during the lifecycle of a specific service instance. Implementations do not need to be synchronized as the logic in AbstractService.stop() prevents re-entrancy. Implementations MUST write this to be robust against failures, including checks for null references -and for the first failure to not stop other attempts to shut down parts of the service.

Overrides:

serviceStop in class AbstractService

Throws:

Exception - if needed -these will be caught and logged.

createEventWriter

protected org.apache.hadoop.mapreduce.jobhistory.EventWriter createEventWriter(Path historyFilePath)
                                                                        throws IOException

Throws:

IOException

setupEventWriter

protected void setupEventWriter(JobId jobId)
                         throws IOException

Create an event writer for the Job represented by the jobID. Writes out the job configuration to the log directory. This should be the first call to history for a job

Parameters:

jobId - the jobId.

Throws:

IOException

closeWriter

public void closeWriter(JobId id)
                 throws IOException

Close the event writer for this id

Throws:

IOException

handle

public void handle(JobHistoryEvent event)

Specified by:

handle in interface EventHandler<JobHistoryEvent>

handleEvent

protected void handleEvent(JobHistoryEvent event)

processEventForJobSummary

public void processEventForJobSummary(HistoryEvent event,
                             JobSummary summary,
                             JobId jobId)

closeEventWriter

protected void closeEventWriter(JobId jobId)
                         throws IOException

Throws:

IOException

processDoneFiles

protected void processDoneFiles(JobId jobId)
                         throws IOException

Throws:

IOException

setForcejobCompletion

public void setForcejobCompletion(boolean forceJobCompletion)