com.technia.tvc.core.util.concurrent

Class ThreadQueue

java.lang.Object

com.technia.tvc.core.util.concurrent.ThreadQueue

public final class ThreadQueue
extends java.lang.Object

Implementation of a simple thread queue that executes Tasks added with the enqueue(Task) method. The number of threads managed by this queue is never less than getMinThreads() nor more than getMaxThreads().

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	ThreadQueue.QueueExecutor Executes Tasks added to the queue.

Constructor Summary

Constructors

Constructor and Description
ThreadQueue()
ThreadQueue(int minThreads, int maxThreads, boolean daemonThreads, long shrinkTimeout, TaskFailureHandler failureHandler)
ThreadQueue(int minThreads, int maxThreads, boolean daemonThreads, long shrinkTimeout, TaskFailureHandler failureHandler, java.lang.String threadGroupId)

Method Summary

Modifier and Type	Method and Description
void	enqueue(Task task) Enqueue the specified task.
int	getActiveThreadCount()
int	getMaxThreads()
int	getMinThreads()
int	getPosition(Task task)
int	getWaitingThreadCount() Returns the number of waiting threads.
protected void	handleFailure(Task task) Handle a failed execution by delegating to the assigned TaskFailureHandler.
boolean	isDaemonThreads()
boolean	isStarted() Returns whether the queue has been started
boolean	isStopped() Returns whether the queue has been stopped, in which case all threads will be stopped.
protected Task	next() Returns the next task ro be executed.
protected java.lang.String	paramString()
void	start() Start the thread queue.
void	stop()
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

ThreadQueue

public ThreadQueue()

ThreadQueue

public ThreadQueue(int minThreads,
                   int maxThreads,
                   boolean daemonThreads,
                   long shrinkTimeout,
                   TaskFailureHandler failureHandler)

ThreadQueue

public ThreadQueue(int minThreads,
                   int maxThreads,
                   boolean daemonThreads,
                   long shrinkTimeout,
                   TaskFailureHandler failureHandler,
                   java.lang.String threadGroupId)

Parameters:

minThreads -

maxThreads -

daemonThreads -

shrinkTimeout -

failureHandler -

threadGroupId -

Since:

2009.2.2

Method Detail

getMinThreads

public int getMinThreads()

getMaxThreads

public int getMaxThreads()

isDaemonThreads

public boolean isDaemonThreads()

getActiveThreadCount

public int getActiveThreadCount()

getWaitingThreadCount

public int getWaitingThreadCount()

Returns the number of waiting threads.

isStarted

public boolean isStarted()

Returns whether the queue has been started

isStopped

public boolean isStopped()

Returns whether the queue has been stopped, in which case all threads will be stopped.

stop

public void stop()

start

public void start()

Start the thread queue. This method will start at least the number of threads specified by the minThreads property.

getPosition

public int getPosition(Task task)

Parameters:

task - The task to get the position for.

Returns:

the position of the task within the queue. If the task is running, then 0 is returned. If the task has completed, failed or for some other reason terminated , then -1 is returned.

enqueue

public void enqueue(Task task)

Enqueue the specified task.

Parameters:

task - The task to enqueue.

Throws:

java.lang.IllegalStateException - If the task already has been added to this or another thread queue or if the task has been canceled already.

next

protected Task next()
             throws java.lang.InterruptedException

Returns the next task ro be executed.

Throws:

java.lang.InterruptedException

handleFailure

protected void handleFailure(Task task)

Handle a failed execution by delegating to the assigned TaskFailureHandler.

paramString

protected java.lang.String paramString()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object