org.apache.hadoop.mapred
Class TaskController

java.lang.Object
  extended by org.apache.hadoop.mapred.TaskController
All Implemented Interfaces:
Configurable
Direct Known Subclasses:
DefaultTaskController

public abstract class TaskController
extends Object
implements Configurable

Controls initialization, finalization and clean up of tasks, and also the launching and killing of task JVMs. This class defines the API for initializing, finalizing and cleaning up of tasks, as also the launching and killing task JVMs. Subclasses of this class will implement the logic required for performing the actual actions.
NOTE: This class is internal only class and not intended for users!!


Nested Class Summary
static class TaskController.DistributedCacheFileContext
          This is used for initializing the private localized files in distributed cache.
static class TaskController.InitializationContext
          NOTE: This class is internal only class and not intended for users!!
 
Field Summary
static org.apache.commons.logging.Log LOG
           
protected  String[] mapredLocalDirs
           
 
Constructor Summary
TaskController()
           
 
Method Summary
 Configuration getConf()
          Return the configuration used by this object.
abstract  void initializeDistributedCacheFile(TaskController.DistributedCacheFileContext context)
          Take task-controller specific actions to initialize the distributed cache file.
abstract  void initializeUser(TaskController.InitializationContext context)
          Initialize user on this TaskTracer in a TaskController specific manner.
 void setConf(Configuration conf)
          Set the configuration to be used by this object.
 void setup()
          Sets up the permissions of the following directories on all the configured disks: mapred-local directories Hadoop log directories
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

LOG

public static final org.apache.commons.logging.Log LOG

mapredLocalDirs

protected String[] mapredLocalDirs
Constructor Detail

TaskController

public TaskController()
Method Detail

getConf

public Configuration getConf()
Description copied from interface: Configurable
Return the configuration used by this object.

Specified by:
getConf in interface Configurable

setConf

public void setConf(Configuration conf)
Description copied from interface: Configurable
Set the configuration to be used by this object.

Specified by:
setConf in interface Configurable

setup

public void setup()
           throws IOException
Sets up the permissions of the following directories on all the configured disks:

Throws:
IOException

initializeDistributedCacheFile

public abstract void initializeDistributedCacheFile(TaskController.DistributedCacheFileContext context)
                                             throws IOException
Take task-controller specific actions to initialize the distributed cache file. This involves setting appropriate permissions for these files so as to secure them to be accessible only their owners.

Parameters:
context -
Throws:
IOException

initializeUser

public abstract void initializeUser(TaskController.InitializationContext context)
                             throws IOException
Initialize user on this TaskTracer in a TaskController specific manner.

Parameters:
context -
Throws:
IOException


Copyright © 2009 The Apache Software Foundation