ml.shifu.guagua.master

Class HookMasterComputable<MASTER_RESULT extends Bytable,WORKER_RESULT extends Bytable>

java.lang.Object

ml.shifu.guagua.master.HookMasterComputable<MASTER_RESULT,WORKER_RESULT>

All Implemented Interfaces:

MasterComputable<MASTER_RESULT,WORKER_RESULT>

public abstract class HookMasterComputable<MASTER_RESULT extends Bytable,WORKER_RESULT extends Bytable>
extends Object
implements MasterComputable<MASTER_RESULT,WORKER_RESULT>

Common MasterComputable abstraction to define setup(MasterContext) and cleanup(MasterContext) hooks.

For classes who extends HookMasterComputable, user can provide its own setup(MasterContext) and cleanup(MasterContext). Guagua will make sure both will be called only once at the beginning and the end of whole process.

Author:

Zhang David (pengzhang@paypal.com)

Constructor Summary

Constructors

Constructor and Description
HookMasterComputable()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	cleanup(MasterContext<MASTER_RESULT,WORKER_RESULT> context) Cleanup method for master computation.
MASTER_RESULT	compute(MasterContext<MASTER_RESULT,WORKER_RESULT> context) Master computation for each iteration.
abstract MASTER_RESULT	doCompute(MasterContext<MASTER_RESULT,WORKER_RESULT> context) Real computation logic excluding some setup and cleanup hooks.
protected void	setup(MasterContext<MASTER_RESULT,WORKER_RESULT> context) Setup method for master computation.

Methods inherited from class java.lang.Object

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

Constructor Detail

HookMasterComputable

public HookMasterComputable()

Method Detail

setup

protected void setup(MasterContext<MASTER_RESULT,WORKER_RESULT> context)

Setup method for master computation. This method will be called once before all iterations.

Parameters:

context - the worker context instance.

compute

public MASTER_RESULT compute(MasterContext<MASTER_RESULT,WORKER_RESULT> context)

Description copied from interface: MasterComputable

Master computation for each iteration.

Specified by:

compute in interface MasterComputable<MASTER_RESULT extends Bytable,WORKER_RESULT extends Bytable>

Parameters:

context - the master context instance which includes worker results and other useful parameters.

Returns:

the master result of each iteration.

doCompute

public abstract MASTER_RESULT doCompute(MasterContext<MASTER_RESULT,WORKER_RESULT> context)

Real computation logic excluding some setup and cleanup hooks.

Parameters:

context - the worker context instance.

Returns:

the master result in that iteration.

cleanup

protected void cleanup(MasterContext<MASTER_RESULT,WORKER_RESULT> context)

Cleanup method for master computation. This method will be called once after all iterations.

Parameters:

context - the worker context instance.

See Also:

for cleanup hook