visad.util
Class ThreadPool

java.lang.Object
  visad.util.ThreadPool

public class ThreadPool
extends Object

A pool of threads (with minimum and maximum limits on the number of threads) which can be used to execute any Runnable tasks.

Constructor Summary

ThreadPool()
Build a thread pool with the default thread name prefix and the default minimum and maximum numbers of threads

ThreadPool(int max)
Build a thread pool with the specified maximum number of threads, and the default thread name prefix and minimum number of threads

ThreadPool(int min, int max)
Build a thread pool with the specified minimum and maximum numbers of threads, and the default thread name prefix

ThreadPool(String prefix)
Build a thread pool with the specified thread name prefix, and the default minimum and maximum numbers of threads

ThreadPool(String prefix, int min, int max)
Build a thread pool with the specified thread name prefix and minimum and maximum numbers of threads

Method Summary

int	getTaskCount() return the number of tasks in the queue and that are running
boolean	isTerminated() Has the thread pool been closed?
void	printPool() Utility method to print out the tasks
void	queue(Runnable r) Add a task to the queue; tasks are executed as soon as a thread is available, in the order in which they are submitted
void	remove(Runnable r)
void	setThreadMaximum(int num) increase the maximum number of pooled threads
void	stopThreads() Stop all threads as soon as all queued tasks are completed
boolean	waitForTasks() wait for currently-running tasks to finish

Methods inherited from class java.lang.Object

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

Constructor Detail

ThreadPool

public ThreadPool()
           throws Exception

Build a thread pool with the default thread name prefix and the default minimum and maximum numbers of threads

Throws:

Exception

ThreadPool

public ThreadPool(String prefix)
           throws Exception

Build a thread pool with the specified thread name prefix, and the default minimum and maximum numbers of threads

Parameters:

prefix -

Throws:

Exception

ThreadPool

public ThreadPool(int max)
           throws Exception

Build a thread pool with the specified maximum number of threads, and the default thread name prefix and minimum number of threads

Parameters:

max -

Throws:

Exception

ThreadPool

public ThreadPool(int min,
                  int max)
           throws Exception

Build a thread pool with the specified minimum and maximum numbers of threads, and the default thread name prefix

Parameters:

min -

max -

Throws:

Exception

ThreadPool

public ThreadPool(String prefix,
                  int min,
                  int max)
           throws Exception

Build a thread pool with the specified thread name prefix and minimum and maximum numbers of threads

Parameters:

prefix -

min -

max -

Throws:

Exception

Method Detail

getTaskCount

public int getTaskCount()

return the number of tasks in the queue and that are running

Returns:

number of queued and active tasks

remove

public void remove(Runnable r)

Parameters:

r -

isTerminated

public boolean isTerminated()

Has the thread pool been closed?

Returns:

true if the pool has been terminated.

printPool

public void printPool()

Utility method to print out the tasks

queue

public void queue(Runnable r)

Add a task to the queue; tasks are executed as soon as a thread is available, in the order in which they are submitted

Parameters:

r -

waitForTasks

public boolean waitForTasks()

wait for currently-running tasks to finish

Returns:

setThreadMaximum

public void setThreadMaximum(int num)
                      throws Exception

increase the maximum number of pooled threads

Parameters:

num -

Throws:

Exception

stopThreads

public void stopThreads()

Stop all threads as soon as all queued tasks are completed