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 591867 2007-11-05 02:20:06Z woonsan $

Author:

Raphaël Luta, David Sean Taylor

Nested Class Summary

(package private) class

WorkerMonitorImpl.RenderingJobTimeoutMonitor

Field Summary

static String	ACCESS_CONTROL_CONTEXT_WORKER_ATTR
protected WorkerMonitorImpl.RenderingJobTimeoutMonitor	jobMonitor Renering Job Timeout monitor
protected static org.apache.commons.logging.Log	log Commons logging
protected int	maxJobsPerWorker Maximum of job processed by a worker before being released
protected int	maxWorkers Maximum number of workers
protected int	minWorkers Minimum number of wokers to create
protected org.apache.jetspeed.util.Queue	queue Job queue
protected int	runningJobs Count of running jobs
protected static long	sCount Static counters for identifying workers
protected int	spareWorkers Minimum amount of spare workers
protected ThreadGroup	tg The thread group used to group all worker threads
protected Stack	workers Stack containing currently idle workers
protected List	workersMonitored Workers to be monitored for timeout checking

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.
int	getAvailableJobsCount() Returns a snapshot of the available jobs
int	getQueuedJobsCount()
int	getRunningJobsCount()
protected 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.
protected 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	start()
void	stop()
void	waitForRenderingJobs(List renderingJobs) Wait for all rendering jobs in the collection to finish successfully or otherwise.

Methods inherited from class java.lang.Object

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

Field Detail

ACCESS_CONTROL_CONTEXT_WORKER_ATTR

public static final String ACCESS_CONTROL_CONTEXT_WORKER_ATTR

log

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

Commons logging

sCount

protected static long sCount

Static counters for identifying workers

runningJobs

protected int runningJobs

Count of running jobs

minWorkers

protected int minWorkers

Minimum number of wokers to create

maxWorkers

protected int maxWorkers

Maximum number of workers

spareWorkers

protected int spareWorkers

Minimum amount of spare workers

maxJobsPerWorker

protected int maxJobsPerWorker

Maximum of job processed by a worker before being released

workers

protected Stack workers

Stack containing currently idle workers

tg

protected ThreadGroup tg

The thread group used to group all worker threads

queue

protected org.apache.jetspeed.util.Queue queue

Job queue

workersMonitored

protected List workersMonitored

Workers to be monitored for timeout checking

jobMonitor

protected WorkerMonitorImpl.RenderingJobTimeoutMonitor jobMonitor

Renering Job Timeout monitor

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

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

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

Retrieves an idle worker

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

waitForRenderingJobs

public void waitForRenderingJobs(List renderingJobs)

Wait for all rendering jobs in the collection to finish successfully or otherwise.

Specified by:

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

Parameters:

renderingJobs - the Collection of rendering job objects to wait for.

release

protected 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.

getQueuedJobsCount

public int getQueuedJobsCount()

Specified by:

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

getAvailableJobsCount

public int getAvailableJobsCount()

Returns a snapshot of the available jobs

Specified by:

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

Returns:

available jobs

getRunningJobsCount

public int getRunningJobsCount()

Specified by:

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