Package org.eclipse.jetty.util.thread

Class QueuedThreadPool

java.lang.Object

org.eclipse.jetty.util.component.AbstractLifeCycle

org.eclipse.jetty.util.component.ContainerLifeCycle

org.eclipse.jetty.util.thread.QueuedThreadPool

All Implemented Interfaces:

java.util.concurrent.Executor, Container, Destroyable, Dumpable, LifeCycle, ThreadPool, ThreadPool.SizedThreadPool, TryExecutor

Direct Known Subclasses:

MonitoredQueuedThreadPool

@ManagedObject("A thread pool")
public class QueuedThreadPool
extends ContainerLifeCycle
implements ThreadPool.SizedThreadPool, Dumpable, TryExecutor

Nested Class Summary

Nested classes/interfaces inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

AbstractLifeCycle.AbstractLifeCycleListener

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.component.Container

Container.InheritedListener, Container.Listener

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.component.LifeCycle

LifeCycle.Listener

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.thread.ThreadPool

ThreadPool.SizedThreadPool

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.thread.TryExecutor

TryExecutor.NoTryExecutor

Field Summary

Fields inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

FAILED, RUNNING, STARTED, STARTING, STOPPED, STOPPING

Fields inherited from interface org.eclipse.jetty.util.thread.TryExecutor

NO_TRY

Constructor Summary

Constructors

Constructor	Description
QueuedThreadPool()
QueuedThreadPool(int maxThreads)
QueuedThreadPool(int maxThreads, int minThreads)
QueuedThreadPool(int maxThreads, int minThreads, int idleTimeout)
QueuedThreadPool(int maxThreads, int minThreads, int idleTimeout, int reservedThreads, java.util.concurrent.BlockingQueue<java.lang.Runnable> queue, java.lang.ThreadGroup threadGroup)
QueuedThreadPool(int maxThreads, int minThreads, int idleTimeout, java.util.concurrent.BlockingQueue<java.lang.Runnable> queue)
QueuedThreadPool(int maxThreads, int minThreads, int idleTimeout, java.util.concurrent.BlockingQueue<java.lang.Runnable> queue, java.lang.ThreadGroup threadGroup)

Method Summary

Modifier and Type	Method	Description
protected void	doStart()	Starts the managed lifecycle beans in the order they were added.
protected void	doStop()	Stops the managed lifecycle beans in the reverse order they were added.
void	dump(java.lang.Appendable out, java.lang.String indent)
java.lang.String	dumpThread(long id)
void	execute(java.lang.Runnable job)
int	getBusyThreads()
int	getIdleThreads()
int	getIdleTimeout()	Get the maximum thread idle time.
int	getLowThreadsThreshold()
int	getMaxThreads()	Get the maximum number of threads.
int	getMinThreads()	Get the minimum number of threads.
java.lang.String	getName()
protected java.util.concurrent.BlockingQueue<java.lang.Runnable>	getQueue()
int	getQueueSize()	Get the size of the job queue.
int	getReservedThreads()	Get the number of reserved threads.
ThreadPoolBudget	getThreadPoolBudget()
int	getThreads()
int	getThreadsPriority()	Get the priority of the pool threads.
boolean	interruptThread(long id)
boolean	isDaemon()
boolean	isDetailedDump()
boolean	isLowOnThreads()	Returns whether this thread pool is low on threads.
void	join()	Blocks until the thread pool is stopped.
protected java.lang.Thread	newThread(java.lang.Runnable runnable)
protected void	removeThread(java.lang.Thread thread)
protected void	runJob(java.lang.Runnable job)	Runs the given job in the current thread.
void	setDaemon(boolean daemon)	Thread Pool should use Daemon Threading.
void	setDetailedDump(boolean detailedDump)
void	setIdleTimeout(int idleTimeout)	Set the maximum thread idle time.
void	setLowThreadsThreshold(int lowThreadsThreshold)
void	setMaxThreads(int maxThreads)	Set the maximum number of threads.
void	setMinThreads(int minThreads)	Set the minimum number of threads.
void	setName(java.lang.String name)
void	setQueue(java.util.concurrent.BlockingQueue<java.lang.Runnable> queue)	Deprecated. pass the queue to the constructor instead
void	setReservedThreads(int reservedThreads)	Set the number of reserved threads.
void	setThreadPoolBudget(ThreadPoolBudget budget)
void	setThreadsPriority(int priority)	Set the priority of the pool threads.
java.lang.String	toString()
boolean	tryExecute(java.lang.Runnable task)	Attempt to execute a task.

Methods inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle

addLifeCycleListener, getState, getState, getStopTimeout, isFailed, isRunning, isStarted, isStarting, isStopped, isStopping, removeLifeCycleListener, start, stop

Methods inherited from class org.eclipse.jetty.util.component.ContainerLifeCycle

addBean, addBean, addBean, addEventListener, addManaged, contains, destroy, dump, dump, dump, dump, dumpBeans, dumpObject, dumpStdErr, dumpThis, getBean, getBeans, getBeans, getContainedBeans, getContainedBeans, isManaged, manage, removeBean, removeBeans, removeEventListener, setBeans, setStopTimeout, start, stop, unmanage, updateBean, updateBean, updateBeans

Methods inherited from interface org.eclipse.jetty.util.component.Dumpable

dump

Methods inherited from interface org.eclipse.jetty.util.component.LifeCycle

start, stop

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eclipse.jetty.util.thread.TryExecutor

asTryExecutor

Constructor Detail

QueuedThreadPool

public QueuedThreadPool()

QueuedThreadPool

public QueuedThreadPool(@Name("maxThreads")
                        int maxThreads)

QueuedThreadPool

public QueuedThreadPool(@Name("maxThreads")
                        int maxThreads,
                        @Name("minThreads")
                        int minThreads)

QueuedThreadPool

public QueuedThreadPool(@Name("maxThreads")
                        int maxThreads,
                        @Name("minThreads")
                        int minThreads,
                        @Name("idleTimeout")
                        int idleTimeout)

QueuedThreadPool

public QueuedThreadPool(@Name("maxThreads")
                        int maxThreads,
                        @Name("minThreads")
                        int minThreads,
                        @Name("idleTimeout")
                        int idleTimeout,
                        @Name("queue")
                        java.util.concurrent.BlockingQueue<java.lang.Runnable> queue)

QueuedThreadPool

public QueuedThreadPool(@Name("maxThreads")
                        int maxThreads,
                        @Name("minThreads")
                        int minThreads,
                        @Name("idleTimeout")
                        int idleTimeout,
                        @Name("queue")
                        java.util.concurrent.BlockingQueue<java.lang.Runnable> queue,
                        @Name("threadGroup")
                        java.lang.ThreadGroup threadGroup)

QueuedThreadPool

public QueuedThreadPool(@Name("maxThreads")
                        int maxThreads,
                        @Name("minThreads")
                        int minThreads,
                        @Name("idleTimeout")
                        int idleTimeout,
                        @Name("reservedThreads")
                        int reservedThreads,
                        @Name("queue")
                        java.util.concurrent.BlockingQueue<java.lang.Runnable> queue,
                        @Name("threadGroup")
                        java.lang.ThreadGroup threadGroup)

Method Detail

getThreadPoolBudget

public ThreadPoolBudget getThreadPoolBudget()

Specified by:

getThreadPoolBudget in interface ThreadPool.SizedThreadPool

Returns:

a ThreadPoolBudget for this sized thread pool, or null of no ThreadPoolBudget can be returned

setThreadPoolBudget

public void setThreadPoolBudget(ThreadPoolBudget budget)

doStart

protected void doStart()
                throws java.lang.Exception

Description copied from class: ContainerLifeCycle

Starts the managed lifecycle beans in the order they were added.

Overrides:

doStart in class ContainerLifeCycle

Throws:

java.lang.Exception

doStop

protected void doStop()
               throws java.lang.Exception

Description copied from class: ContainerLifeCycle

Stops the managed lifecycle beans in the reverse order they were added.

Overrides:

doStop in class ContainerLifeCycle

Throws:

java.lang.Exception

setDaemon

public void setDaemon(boolean daemon)

Thread Pool should use Daemon Threading.

Parameters:

daemon - true to enable delegation

See Also:

Thread.setDaemon(boolean)

setIdleTimeout

public void setIdleTimeout(int idleTimeout)

Set the maximum thread idle time. Threads that are idle for longer than this period may be stopped.

Parameters:

idleTimeout - Max idle time in ms.

See Also:

getIdleTimeout()

setMaxThreads

public void setMaxThreads(int maxThreads)

Set the maximum number of threads.

Specified by:

setMaxThreads in interface ThreadPool.SizedThreadPool

Parameters:

maxThreads - maximum number of threads.

See Also:

getMaxThreads()

setMinThreads

public void setMinThreads(int minThreads)

Set the minimum number of threads.

Specified by:

setMinThreads in interface ThreadPool.SizedThreadPool

Parameters:

minThreads - minimum number of threads

See Also:

getMinThreads()

setReservedThreads

public void setReservedThreads(int reservedThreads)

Set the number of reserved threads.

Parameters:

reservedThreads - number of reserved threads or -1 for heuristically determined

See Also:

getReservedThreads()

setName

public void setName(java.lang.String name)

Parameters:

name - Name of this thread pool to use when naming threads.

setThreadsPriority

public void setThreadsPriority(int priority)

Set the priority of the pool threads.

Parameters:

priority - the new thread priority.

getIdleTimeout

@ManagedAttribute("maximum time a thread may be idle in ms")
public int getIdleTimeout()

Get the maximum thread idle time.

Returns:

Max idle time in ms.

See Also:

setIdleTimeout(int)

getMaxThreads

@ManagedAttribute("maximum number of threads in the pool")
public int getMaxThreads()

Get the maximum number of threads.

Specified by:

getMaxThreads in interface ThreadPool.SizedThreadPool

Returns:

maximum number of threads.

See Also:

setMaxThreads(int)

getMinThreads

@ManagedAttribute("minimum number of threads in the pool")
public int getMinThreads()

Get the minimum number of threads.

Specified by:

getMinThreads in interface ThreadPool.SizedThreadPool

Returns:

minimum number of threads.

See Also:

setMinThreads(int)

getReservedThreads

@ManagedAttribute("the number of reserved threads in the pool")
public int getReservedThreads()

Get the number of reserved threads.

Returns:

number of reserved threads or or -1 for heuristically determined

See Also:

setReservedThreads(int)

getName

@ManagedAttribute("name of the thread pool")
public java.lang.String getName()

Returns:

The name of the this thread pool

getThreadsPriority

@ManagedAttribute("priority of threads in the pool")
public int getThreadsPriority()

Get the priority of the pool threads.

Returns:

the priority of the pool threads.

getQueueSize

@ManagedAttribute("size of the job queue")
public int getQueueSize()

Get the size of the job queue.

Returns:

Number of jobs queued waiting for a thread

isDaemon

@ManagedAttribute("thread pool uses daemon threads")
public boolean isDaemon()

Returns:

whether this thread pool is using daemon threads

See Also:

Thread.setDaemon(boolean)

isDetailedDump

@ManagedAttribute("reports additional details in the dump")
public boolean isDetailedDump()

setDetailedDump

public void setDetailedDump(boolean detailedDump)

getLowThreadsThreshold

@ManagedAttribute("threshold at which the pool is low on threads")
public int getLowThreadsThreshold()

setLowThreadsThreshold

public void setLowThreadsThreshold(int lowThreadsThreshold)

execute

public void execute(java.lang.Runnable job)

Specified by:

execute in interface java.util.concurrent.Executor

Specified by:

execute in interface TryExecutor

tryExecute

public boolean tryExecute(java.lang.Runnable task)

Description copied from interface: TryExecutor

Attempt to execute a task.

Specified by:

tryExecute in interface TryExecutor

Parameters:

task - The task to be executed

Returns:

True IFF the task has been given directly to a thread to execute. The task cannot be queued pending the later availability of a Thread.

join

public void join()
          throws java.lang.InterruptedException

Blocks until the thread pool is stopped.

Specified by:

join in interface ThreadPool

Throws:

java.lang.InterruptedException - if thread was interrupted

getThreads

@ManagedAttribute("number of threads in the pool")
public int getThreads()

Specified by:

getThreads in interface ThreadPool

Returns:

the total number of threads currently in the pool

getIdleThreads

@ManagedAttribute("number of idle threads in the pool")
public int getIdleThreads()

Specified by:

getIdleThreads in interface ThreadPool

Returns:

the number of idle threads in the pool

getBusyThreads

@ManagedAttribute("number of busy threads in the pool")
public int getBusyThreads()

Returns:

the number of busy threads in the pool

isLowOnThreads

@ManagedAttribute(value="thread pool is low on threads",
                  readonly=true)
public boolean isLowOnThreads()

Returns whether this thread pool is low on threads.

The current formula is:

 maxThreads - threads + idleThreads - queueSize <= lowThreadsThreshold
 

Specified by:

isLowOnThreads in interface ThreadPool

Returns:

whether the pool is low on threads

See Also:

getLowThreadsThreshold()

newThread

protected java.lang.Thread newThread(java.lang.Runnable runnable)

removeThread

protected void removeThread(java.lang.Thread thread)

dump

public void dump(java.lang.Appendable out,
                 java.lang.String indent)
          throws java.io.IOException

Specified by:

dump in interface Dumpable

Overrides:

dump in class ContainerLifeCycle

Throws:

java.io.IOException

toString

public java.lang.String toString()

Overrides:

toString in class AbstractLifeCycle

runJob

protected void runJob(java.lang.Runnable job)

Runs the given job in the current thread.

Subclasses may override to perform pre/post actions before/after the job is run.

Parameters:

job - the job to run

getQueue

protected java.util.concurrent.BlockingQueue<java.lang.Runnable> getQueue()

Returns:

the job queue

setQueue

@Deprecated
public void setQueue(java.util.concurrent.BlockingQueue<java.lang.Runnable> queue)

Deprecated. pass the queue to the constructor instead

Parameters:

queue - the job queue

interruptThread

@ManagedOperation("interrupts a pool thread")
public boolean interruptThread(@Name("id")
                               long id)

Parameters:

id - the thread ID to interrupt.

Returns:

true if the thread was found and interrupted.

dumpThread

@ManagedOperation("dumps a pool thread stack")
public java.lang.String dumpThread(@Name("id")
                                   long id)

Parameters:

id - the thread ID to interrupt.

Returns:

the stack frames dump