Module org.eclipse.jetty.util

Package org.eclipse.jetty.util.thread

Class VirtualThreadPool

java.lang.Object

org.eclipse.jetty.util.component.AbstractLifeCycle

org.eclipse.jetty.util.component.ContainerLifeCycle

org.eclipse.jetty.util.thread.VirtualThreadPool

All Implemented Interfaces:

Executor, Container, Destroyable, Dumpable, Dumpable.DumpableContainer, LifeCycle, ThreadPool, TryExecutor, VirtualThreads.Configurable

@ManagedObject("A thread non-pool for virtual threads")
public class VirtualThreadPool
extends ContainerLifeCycle
implements ThreadPool, Dumpable, TryExecutor, VirtualThreads.Configurable

An implementation of ThreadPool interface that does not pool, but instead uses VirtualThreads.

It is possible to specify the max number of concurrent virtual threads that can be spawned, to help limiting resource usage in applications, especially in case of load spikes, where an unlimited number of virtual threads may be spawned, compete for resources, and eventually bring the system down due to memory exhaustion.

Nested Class Summary

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

AbstractLifeCycle.AbstractLifeCycleListener, AbstractLifeCycle.StopException

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.Dumpable

Dumpable.DumpableContainer

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, STARTED, STARTING, STOPPED, STOPPING

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

KEY

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

NO_TRY

Constructor Summary

Constructors

Constructor	Description
VirtualThreadPool()
VirtualThreadPool(int maxThreads)

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	execute(Runnable task)
int	getIdleThreads()
int	getMaxThreads()
String	getName()
int	getThreads()
Executor	getVirtualThreadsExecutor()
boolean	isDetailedDump()
boolean	isLowOnThreads()
boolean	isTracking()	Get if this pool is tracking virtual threads.
void	join()	Blocks until the thread pool is stopped.
void	setDetailedDump(boolean detailedDump)
void	setMaxThreads(int maxThreads)
void	setName(String name)	Sets the name of this thread pool, used as a prefix for the thread names.
void	setTracking(boolean tracking)
void	setVirtualThreadsExecutor(Executor executor)
boolean	tryExecute(Runnable task)	Attempt to execute a task.

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

addBean, addBean, addEventListener, addManaged, contains, destroy, dump, dump, dump, dumpObjects, dumpStdErr, getBean, getBeans, getBeans, getContainedBeans, getContainedBeans, installBean, installBean, isAuto, isManaged, isUnmanaged, manage, removeBean, removeBeans, removeEventListener, setBeans, start, stop, unmanage, updateBean, updateBean, updateBeans, updateBeans

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

getEventListeners, getState, getState, isFailed, isRunning, isStarted, isStarting, isStopped, isStopping, setEventListeners, start, stop, toString

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.component.Container

getCachedBeans, getEventListeners

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

dump, dump, dumpSelf

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

isDumpable

Methods inherited from interface org.eclipse.jetty.util.VirtualThreads.Configurable

isUseVirtualThreads, setUseVirtualThreads

Constructor Details

VirtualThreadPool

public VirtualThreadPool()

VirtualThreadPool

public VirtualThreadPool(int maxThreads)

Method Details

getName

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

Returns:

the name of this thread pool

setName

public void setName(String name)

Sets the name of this thread pool, used as a prefix for the thread names.

Parameters:

name - the name of this thread pool

getMaxThreads

@ManagedAttribute("The max number of concurrent virtual threads")
public int getMaxThreads()

Returns:

the maximum number of concurrent virtual threads

setMaxThreads

public void setMaxThreads(int maxThreads)

Parameters:

maxThreads - the maximum number of concurrent virtual threads

isTracking

@ManagedAttribute("Whether virtual threads are tracked")
public boolean isTracking()

Get if this pool is tracking virtual threads.

Returns:

true if the virtual threads will be tracked.

See Also:

• TrackingExecutor

setTracking

public void setTracking(boolean tracking)

isDetailedDump

@ManagedAttribute("Whether to report additional details in the dump")
public boolean isDetailedDump()

setDetailedDump

public void setDetailedDump(boolean detailedDump)

doStart

protected void doStart()
                throws Exception

Description copied from class: ContainerLifeCycle

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

Overrides:

doStart in class ContainerLifeCycle

Throws:

Exception - If there was a problem starting. Will cause a transition to FAILED state

doStop

protected void doStop()
               throws Exception

Description copied from class: ContainerLifeCycle

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

Overrides:

doStop in class ContainerLifeCycle

Throws:

Exception - If there was a problem stopping. Will cause a transition to FAILED state

getVirtualThreadsExecutor

public Executor getVirtualThreadsExecutor()

Specified by:

getVirtualThreadsExecutor in interface VirtualThreads.Configurable

Returns:

the Executor to use to execute tasks in virtual threads

setVirtualThreadsExecutor

public void setVirtualThreadsExecutor(Executor executor)

Specified by:

setVirtualThreadsExecutor in interface VirtualThreads.Configurable

Parameters:

executor - the Executor to use to execute tasks in virtual threads

See Also:

• VirtualThreads.areSupported()

join

public void join()
          throws InterruptedException

Description copied from interface: ThreadPool

Blocks until the thread pool is stopped.

Specified by:

join in interface ThreadPool

Throws:

InterruptedException - if thread was interrupted

getThreads

public int getThreads()

Specified by:

getThreads in interface ThreadPool

Returns:

The total number of threads currently in the pool

getIdleThreads

public int getIdleThreads()

Specified by:

getIdleThreads in interface ThreadPool

Returns:

The number of idle threads in the pool

isLowOnThreads

public boolean isLowOnThreads()

Specified by:

isLowOnThreads in interface ThreadPool

Returns:

True if the pool is low on threads

tryExecute

public boolean tryExecute(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.

execute

public void execute(Runnable task)

Specified by:

execute in interface Executor

Specified by:

execute in interface TryExecutor