de.spieleck.util
Class ThreadPool

java.lang.Object
  java.lang.ThreadGroup
      de.spieleck.util.ThreadPool

public class ThreadPool

extends java.lang.ThreadGroup

Implement a thread pool for dispatching arbitrary many jobs to a fixed number of workers. The tasks must implement Runnable and are provided by a TaskSource.

Version:

0.0

Author:

fsn

Nested Class Summary

protected class

ThreadPool.WorkerThread Inner class to actually do something.

Field Summary

protected int	critical How many tasks are still running?
protected java.util.Map	eHandlers Do we have special exception handlers?
protected int	runningTasks How many tasks are still running?
protected TaskSource	tSource The actual source of work

Constructor Summary

ThreadPool(int size, TaskSource tSource)
Construct a pool with a choosable number of threads.

ThreadPool(TaskSource tSource)
Construct a pool with a default number of threads.

Method Summary

void	addExceptionHandler(java.lang.Class e, ExceptionHandler handler) Protected attach a new Exception handler.
protected void	finalize() Do something useful on finalization time
int	getRunningTasks() How many tasks are still working
protected java.lang.Runnable	getTask() Fetch the next assignment.
void	join() Wait until all jobs are done.
void	uncaughtException(java.lang.Thread t, java.lang.Throwable e) customizable exception handling.
void	waitDone() Wait until we have started doing something.
void	waitStart() Wait until we have started doing something.

Methods inherited from class java.lang.ThreadGroup

activeCount, activeGroupCount, allowThreadSuspension, checkAccess, destroy, enumerate, enumerate, enumerate, enumerate, getMaxPriority, getName, getParent, interrupt, isDaemon, isDestroyed, list, parentOf, resume, setDaemon, setMaxPriority, stop, suspend, toString

Methods inherited from class java.lang.Object

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

Field Detail

runningTasks

protected int runningTasks

How many tasks are still running?

critical

protected int critical

How many tasks are still running?

eHandlers

protected java.util.Map eHandlers

Do we have special exception handlers?

tSource

protected TaskSource tSource

The actual source of work

Constructor Detail

ThreadPool

public ThreadPool(TaskSource tSource)

Construct a pool with a default number of threads.

ThreadPool

public ThreadPool(int size,
                  TaskSource tSource)

Construct a pool with a choosable number of threads.

Method Detail

getTask

protected java.lang.Runnable getTask()

Fetch the next assignment.

addExceptionHandler

public void addExceptionHandler(java.lang.Class e,
                                ExceptionHandler handler)

Protected attach a new Exception handler.

waitStart

public void waitStart()
               throws java.lang.InterruptedException

Wait until we have started doing something.

Throws:

java.lang.InterruptedException

waitDone

public void waitDone()
              throws java.lang.InterruptedException

Wait until we have started doing something.

Throws:

java.lang.InterruptedException

join

public void join()

Wait until all jobs are done. That is, we have to wait for both, that every single task is done and that there are no tasks remaining any more. But in the very beginning we assume there is something to do and wait for at least one task!

getRunningTasks

public int getRunningTasks()

How many tasks are still working

uncaughtException

public void uncaughtException(java.lang.Thread t,
                              java.lang.Throwable e)

customizable exception handling.

finalize

protected void finalize()
                 throws java.lang.Throwable

Do something useful on finalization time

Throws:

java.lang.Throwable