ml.shifu.guagua.worker

Class HookWorkerComputable<MASTER_RESULT extends Bytable,WORKER_RESULT extends Bytable>

java.lang.Object

ml.shifu.guagua.worker.HookWorkerComputable<MASTER_RESULT,WORKER_RESULT>

All Implemented Interfaces:

WorkerComputable<MASTER_RESULT,WORKER_RESULT>

public abstract class HookWorkerComputable<MASTER_RESULT extends Bytable,WORKER_RESULT extends Bytable>
extends Object
implements WorkerComputable<MASTER_RESULT,WORKER_RESULT>

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

For classes who extends HookWorkerComputable, user can provide its own setup(WorkerContext) and cleanup(WorkerContext). 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
HookWorkerComputable()

Method Summary

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

HookWorkerComputable

public HookWorkerComputable()

Method Detail

setup

protected void setup(WorkerContext<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 WORKER_RESULT compute(WorkerContext<MASTER_RESULT,WORKER_RESULT> context)

Description copied from interface: WorkerComputable

Worker computation for each iteration.

Specified by:

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

Parameters:

context - the worker context instance which includes worker info, master result of last iteration or other useful into for each iteration.

Returns:

the worker result of each iteration.

doCompute

public abstract WORKER_RESULT doCompute(WorkerContext<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(WorkerContext<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