Package jadex.concurrent

Class MonitoredThreadPoolExecutor

java.lang.Object

java.util.concurrent.AbstractExecutorService

java.util.concurrent.ThreadPoolExecutor

jadex.concurrent.MonitoredThreadPoolExecutor

All Implemented Interfaces:

Executor, ExecutorService

public class MonitoredThreadPoolExecutor
extends ThreadPoolExecutor

Thread pool executor based on the Java 5 ThreadPoolExecutor class. Uses a monitoring thread to monitor pool thread behavior to adjust pool size.

Nested Class Summary

Nested classes/interfaces inherited from class java.util.concurrent.ThreadPoolExecutor

ThreadPoolExecutor.AbortPolicy, ThreadPoolExecutor.CallerRunsPolicy, ThreadPoolExecutor.DiscardOldestPolicy, ThreadPoolExecutor.DiscardPolicy

Field Summary

Fields

Modifier and Type	Field	Description
protected static final boolean	AGGRESSIVE	If true, be more aggressive when creating threads.
protected static final int	BASE_TCNT	Starting number of threads.
protected static final boolean	DEBUG	Print debug messages
protected AtomicInteger	idle	Number of idle threads in the pool.
protected static final long	LOSS_THRESHOLD	Threshold after which a _blocking_ thread is considered stolen.
protected static final long	LOSS_THRESHOLD_BUSY	Threshold after which a _non-blocking_ thread is considered stolen.
protected static final long	MONIT_CYCLE	Min.
protected static final int	MONIT_THRESHOLD	Threshold for activating monitoring.
protected boolean	monitoring	Flag for monitoring thread activity.
protected Semaphore	monitoringlock	The lock for the monitoring thread.
protected Thread	monitthread	The monitoring thread.
protected MonitoredThread[]	threads	The threads in the pool.

Constructor Summary

Constructors

Constructor	Description
MonitoredThreadPoolExecutor()

Method Summary

Modifier and Type	Method	Description
protected void	borrow(MonitoredThread thread)	Borrows the thread.
protected void	borrowNoUnpark(MonitoredThread thread)	Borrows the thread without unparking.
protected static final MonitoredThread	currentThread()	Gets the current MonitoredThread, for convenience.
void	execute(Runnable command)
protected static final void	releaseLock(Semaphore lock)	Releases the semaphore, includes null check.

Methods inherited from class java.util.concurrent.ThreadPoolExecutor

afterExecute, allowCoreThreadTimeOut, allowsCoreThreadTimeOut, awaitTermination, beforeExecute, finalize, getActiveCount, getCompletedTaskCount, getCorePoolSize, getKeepAliveTime, getLargestPoolSize, getMaximumPoolSize, getPoolSize, getQueue, getRejectedExecutionHandler, getTaskCount, getThreadFactory, isShutdown, isTerminated, isTerminating, prestartAllCoreThreads, prestartCoreThread, purge, remove, setCorePoolSize, setKeepAliveTime, setMaximumPoolSize, setRejectedExecutionHandler, setThreadFactory, shutdown, shutdownNow, terminated, toString

Methods inherited from class java.util.concurrent.AbstractExecutorService

invokeAll, invokeAll, invokeAny, invokeAny, newTaskFor, newTaskFor, submit, submit, submit

Methods inherited from class java.lang.Object

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

Field Details

DEBUG

protected static final boolean DEBUG

Print debug messages

See Also:

• Constant Field Values

AGGRESSIVE

protected static final boolean AGGRESSIVE

If true, be more aggressive when creating threads.

See Also:

• Constant Field Values

MONIT_THRESHOLD

protected static final int MONIT_THRESHOLD

Threshold for activating monitoring.

BASE_TCNT

protected static final int BASE_TCNT

Starting number of threads.

MONIT_CYCLE

protected static final long MONIT_CYCLE

Min. wait time between monitoring cycles.

See Also:

• Constant Field Values

LOSS_THRESHOLD

protected static final long LOSS_THRESHOLD

Threshold after which a _blocking_ thread is considered stolen.

See Also:

• Constant Field Values

LOSS_THRESHOLD_BUSY

protected static final long LOSS_THRESHOLD_BUSY

Threshold after which a _non-blocking_ thread is considered stolen.

See Also:

• Constant Field Values

idle

protected AtomicInteger idle

Number of idle threads in the pool.

threads

protected volatile MonitoredThread[] threads

The threads in the pool.

monitoringlock

protected volatile Semaphore monitoringlock

The lock for the monitoring thread.

monitthread

protected Thread monitthread

The monitoring thread.

monitoring

protected boolean monitoring

Flag for monitoring thread activity.

Constructor Details

MonitoredThreadPoolExecutor

public MonitoredThreadPoolExecutor()

Method Details

execute

public void execute(Runnable command)

Specified by:

execute in interface Executor

Overrides:

execute in class ThreadPoolExecutor

borrow

protected void borrow(MonitoredThread thread)

Borrows the thread.

Parameters:

thread - Thre thread being borrowed.

borrowNoUnpark

protected void borrowNoUnpark(MonitoredThread thread)

Borrows the thread without unparking.

Parameters:

thread - Thre thread being borrowed.

releaseLock

protected static final void releaseLock(Semaphore lock)

Releases the semaphore, includes null check.

Parameters:

lock - The lock.

currentThread

protected static final MonitoredThread currentThread()

Gets the current MonitoredThread, for convenience.

Returns:

Current MonitoredThread.