org.apache.jetspeed.aggregator.impl
Class WorkerMonitorImpl

java.lang.Object
  org.apache.jetspeed.aggregator.impl.WorkerMonitorImpl

All Implemented Interfaces:

org.apache.jetspeed.aggregator.WorkerMonitor

public class WorkerMonitorImpl

extends Object

implements org.apache.jetspeed.aggregator.WorkerMonitor

The WorkerMonitor is responsible for dispatching jobs to workers It uses an Apache HTTPd configuration style of min/max/spare workers threads to throttle the rendering work. If jobs come in faster that processing, they are stored in a queue which is flushed periodically by a QueueMonitor.

Version:

$Id: WorkerMonitorImpl.java 279462 2005-09-07 23:44:03Z taylor $

Author:

Rapha?l Luta, David Sean Taylor

Field Summary

protected static org.apache.commons.logging.Log	log Commons logging
private int	maxJobsPerWorker Maximum of job processed by a worker before being released
private int	maxWorkers Maximum number of workers
private int	minWorkers Minimum number of wokers to create
private org.apache.jetspeed.util.Queue	queue Job queue
private static long	sCount Static counters for identifying workers
private int	spareWorkers Minimum amount of spare workers
private ThreadGroup	tg The thread group used to group all worker threads
private Stack	workers Stack containing currently idle workers

Constructor Summary

WorkerMonitorImpl(int minWorkers, int maxWorkers, int spareWorkers, int maxJobsPerWorker)

Method Summary

protected void	addWorkers(int wCount) Create the request number of workers and add them to list of available workers.
org.apache.jetspeed.aggregator.Worker	getWorker() Retrieves an idle worker
void	process(org.apache.jetspeed.aggregator.RenderingJob job) Assign a job to a worker and execute it or queue the job if no worker is available.
void	release(org.apache.jetspeed.aggregator.Worker worker) Put back the worker in the idle queue unless there are pending jobs and worker can still be committed to a new job before being released.
void	setQueue(org.apache.jetspeed.util.Queue queue)
void	start()
void	stop()

Methods inherited from class java.lang.Object

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

Field Detail

log

protected static final org.apache.commons.logging.Log log

Commons logging

sCount

private static long sCount

Static counters for identifying workers

minWorkers

private int minWorkers

Minimum number of wokers to create

maxWorkers

private int maxWorkers

Maximum number of workers

spareWorkers

private int spareWorkers

Minimum amount of spare workers

maxJobsPerWorker

private int maxJobsPerWorker

Maximum of job processed by a worker before being released

workers

private Stack workers

Stack containing currently idle workers

tg

private ThreadGroup tg

The thread group used to group all worker threads

queue

private org.apache.jetspeed.util.Queue queue

Job queue

Constructor Detail

WorkerMonitorImpl

public WorkerMonitorImpl(int minWorkers,
                         int maxWorkers,
                         int spareWorkers,
                         int maxJobsPerWorker)

Method Detail

start

public void start()

Specified by:

start in interface org.apache.jetspeed.aggregator.WorkerMonitor

stop

public void stop()

Specified by:

stop in interface org.apache.jetspeed.aggregator.WorkerMonitor

setQueue

public void setQueue(org.apache.jetspeed.util.Queue queue)

Specified by:

setQueue in interface org.apache.jetspeed.aggregator.WorkerMonitor

addWorkers

protected void addWorkers(int wCount)

Create the request number of workers and add them to list of available workers.

Parameters:

wCount - the number of workers to create

getWorker

public org.apache.jetspeed.aggregator.Worker getWorker()

Retrieves an idle worker

Specified by:

getWorker in interface org.apache.jetspeed.aggregator.WorkerMonitor

Returns:

a Worker from the idle pool or null if non available

process

public void process(org.apache.jetspeed.aggregator.RenderingJob job)

Assign a job to a worker and execute it or queue the job if no worker is available.

Specified by:

process in interface org.apache.jetspeed.aggregator.WorkerMonitor

Parameters:

job - the Job to process

release

public void release(org.apache.jetspeed.aggregator.Worker worker)

Put back the worker in the idle queue unless there are pending jobs and worker can still be committed to a new job before being released.

Specified by:

release in interface org.apache.jetspeed.aggregator.WorkerMonitor