org.jscience.util
Class ThreadWorker

java.lang.Object
  java.lang.Thread
      org.jscience.util.ThreadWorker

All Implemented Interfaces:

java.lang.Runnable, java.util.concurrent.Executor

public class ThreadWorker
extends java.lang.Thread
implements java.util.concurrent.Executor

ThreadWorker runs tasks in a separate thread, where the tasks are queued up and performed one by one. Java 1.5 makes this class somewhat obsolete, but it's still there as it has been used elsewhere in this framework. Since the JDK 1.5 FCS, this implementation is adopted to implement Executor.

Since:

04/28/2004

Nested Class Summary

static interface

ThreadWorker.Listener listens for tasks run by a ThreadWorker to be finished

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

ThreadWorker()
Creates a new ThreadWorker object.

ThreadWorker(java.lang.String name)
Creates a new ThreadWorker object.

ThreadWorker(java.lang.ThreadGroup group, java.lang.String name)
Creates a new ThreadWorker object.

Method Summary

boolean	addListener(ThreadWorker.Listener listener) DOCUMENT ME!
void	endAfterCurrent() ends the thread after the current task ended; the effect is irreversible
void	endAfterLast() ends the thread after the last queued task ended; the effect is irreversible
void	execute(java.lang.Runnable task) calls runTask(task); this method enables usability with jdk1.5
java.lang.Runnable	getCurrentTask() returns the Runnable object currently executed by this ThreadWorker
long	getCurrentTaskRunningTime() if no task is currently running, -1 is returned.
ThreadWorker.Listener[]	getListeners() DOCUMENT ME!
int	getQueueSize() returns the number of Runnable objects waiting to be executed
int	getTaskCount() returns the number of tasks that have been executed (including the current one)
java.lang.Runnable[]	getTasks() returns all tasks currently in the queue (including the current one)
long	getTotalRunningTime() excludes time where this thread is waiting for requests
boolean	isIdle() DOCUMENT ME!
boolean	removeListener(ThreadWorker.Listener listener) DOCUMENT ME!
boolean	removeTask(java.lang.Runnable task) DOCUMENT ME!
void	run() should be called only once through start()
int	runTask(java.lang.Runnable task) runs the given task immediately after all previous tasks have finished - once the ThreadWorker has been started.
boolean	willEndAfterCurrent() DOCUMENT ME!
boolean	willEndAfterLast() DOCUMENT ME!

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

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

Constructor Detail

ThreadWorker

public ThreadWorker()

Creates a new ThreadWorker object.

ThreadWorker

public ThreadWorker(java.lang.String name)

Creates a new ThreadWorker object.

Parameters:

name - DOCUMENT ME!

ThreadWorker

public ThreadWorker(java.lang.ThreadGroup group,
                    java.lang.String name)

Creates a new ThreadWorker object.

Parameters:

group - DOCUMENT ME!

name - DOCUMENT ME!

Method Detail

addListener

public boolean addListener(ThreadWorker.Listener listener)

DOCUMENT ME!

Parameters:

listener - DOCUMENT ME!

Returns:

DOCUMENT ME!

removeListener

public boolean removeListener(ThreadWorker.Listener listener)

DOCUMENT ME!

Parameters:

listener - DOCUMENT ME!

Returns:

DOCUMENT ME!

getListeners

public ThreadWorker.Listener[] getListeners()

DOCUMENT ME!

Returns:

DOCUMENT ME!

getCurrentTask

public java.lang.Runnable getCurrentTask()

returns the Runnable object currently executed by this ThreadWorker

Returns:

DOCUMENT ME!

getQueueSize

public int getQueueSize()

returns the number of Runnable objects waiting to be executed

Returns:

DOCUMENT ME!

isIdle

public boolean isIdle()

DOCUMENT ME!

Returns:

DOCUMENT ME!

getTasks

public java.lang.Runnable[] getTasks()

returns all tasks currently in the queue (including the current one)

Returns:

DOCUMENT ME!

removeTask

public boolean removeTask(java.lang.Runnable task)
                   throws java.lang.IllegalStateException

DOCUMENT ME!

Parameters:

task - DOCUMENT ME!

Returns:

DOCUMENT ME!

Throws:

java.lang.IllegalStateException - if the given task is currently running

getTaskCount

public int getTaskCount()

returns the number of tasks that have been executed (including the current one)

Returns:

DOCUMENT ME!

getTotalRunningTime

public long getTotalRunningTime()

excludes time where this thread is waiting for requests

Returns:

DOCUMENT ME!

getCurrentTaskRunningTime

public long getCurrentTaskRunningTime()

if no task is currently running, -1 is returned.

Returns:

DOCUMENT ME!

execute

public void execute(java.lang.Runnable task)

calls runTask(task); this method enables usability with jdk1.5

Specified by:

execute in interface java.util.concurrent.Executor

Parameters:

task - DOCUMENT ME!

runTask

public int runTask(java.lang.Runnable task)
            throws java.lang.IllegalStateException

runs the given task immediately after all previous tasks have finished - once the ThreadWorker has been started.

Parameters:

task - DOCUMENT ME!

Returns:

the number of tasks currently in the queue (including the given one)

Throws:

java.lang.IllegalStateException - if the task has no chance anymore of being run

run

public void run()
         throws java.lang.IllegalThreadStateException

should be called only once through start()

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread

Throws:

java.lang.IllegalThreadStateException - if the method is called through anything but start() once

endAfterLast

public void endAfterLast()

ends the thread after the last queued task ended; the effect is irreversible

endAfterCurrent

public void endAfterCurrent()

ends the thread after the current task ended; the effect is irreversible

willEndAfterCurrent

public boolean willEndAfterCurrent()

DOCUMENT ME!

Returns:

DOCUMENT ME!

willEndAfterLast

public boolean willEndAfterLast()

DOCUMENT ME!

Returns:

DOCUMENT ME!