org.springframework.scheduling.concurrent
Class ThreadPoolTaskExecutor

java.lang.Object
  org.springframework.util.CustomizableThreadCreator
      org.springframework.scheduling.concurrent.CustomizableThreadFactory
          org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor

All Implemented Interfaces:

Executor, ThreadFactory, BeanNameAware, DisposableBean, InitializingBean, TaskExecutor, SchedulingTaskExecutor

public class ThreadPoolTaskExecutor
extends CustomizableThreadFactory
implements SchedulingTaskExecutor, Executor, BeanNameAware, InitializingBean, DisposableBean

JavaBean that allows for configuring a JDK 1.5 ThreadPoolExecutor in bean style (through its "corePoolSize", "maxPoolSize", "keepAliveSeconds", "queueCapacity" properties), exposing it as a Spring TaskExecutor. This is an alternative to configuring a ThreadPoolExecutor instance directly using constructor injection, with a separate ConcurrentTaskExecutor adapter wrapping it.

For any custom needs, in particular for defining a ScheduledThreadPoolExecutor, it is recommended to use a straight definition of the Executor instance or a factory method definition that points to the JDK 1.5 Executors class. To expose such a raw Executor as a Spring TaskExecutor, simply wrap it with a ConcurrentTaskExecutor adapter.

NOTE: This class implements Spring's TaskExecutor interface as well as the JDK 1.5 Executor interface, with the former being the primary interface, the other just serving as secondary convenience. For this reason, the exception handling follows the TaskExecutor contract rather than the Executor contract, in particular regarding the TaskRejectedException.

Since:

2.0

Author:

Juergen Hoeller

See Also:

TaskExecutor, Executor, ThreadPoolExecutor, ScheduledThreadPoolExecutor, Executors, ConcurrentTaskExecutor

Field Summary

protected Log

logger

Constructor Summary

ThreadPoolTaskExecutor()

Method Summary

void	afterPropertiesSet() Calls initialize() after the container applied all property values.
protected BlockingQueue	createQueue(int queueCapacity) Create the BlockingQueue to use for the ThreadPoolExecutor.
void	destroy() Calls shutdown when the BeanFactory destroys the task executor instance.
void	execute(Runnable task) Implementation of both the JDK 1.5 Executor interface and the Spring TaskExecutor interface, delegating to the ThreadPoolExecutor instance.
int	getActiveCount() Return the number of currently active threads.
int	getCorePoolSize() Return the ThreadPoolExecutor's core pool size.
int	getKeepAliveSeconds() Return the ThreadPoolExecutor's keep-alive seconds.
int	getMaxPoolSize() Return the ThreadPoolExecutor's maximum pool size.
int	getPoolSize() Return the current pool size.
ThreadPoolExecutor	getThreadPoolExecutor() Return the underlying ThreadPoolExecutor for native access.
void	initialize() Creates the BlockingQueue and the ThreadPoolExecutor.
boolean	prefersShortLivedTasks() This task executor prefers short-lived work units.
void	setAllowCoreThreadTimeOut(boolean allowCoreThreadTimeOut) Specify whether to allow core threads to time out.
void	setBeanName(String name) Set the name of the bean in the bean factory that created this bean.
void	setCorePoolSize(int corePoolSize) Set the ThreadPoolExecutor's core pool size.
void	setKeepAliveSeconds(int keepAliveSeconds) Set the ThreadPoolExecutor's keep-alive seconds.
void	setMaxPoolSize(int maxPoolSize) Set the ThreadPoolExecutor's maximum pool size.
void	setQueueCapacity(int queueCapacity) Set the capacity for the ThreadPoolExecutor's BlockingQueue.
void	setRejectedExecutionHandler(RejectedExecutionHandler rejectedExecutionHandler) Set the RejectedExecutionHandler to use for the ThreadPoolExecutor.
void	setThreadFactory(ThreadFactory threadFactory) Set the ThreadFactory to use for the ThreadPoolExecutor's thread pool.
void	setThreadNamePrefix(String threadNamePrefix) Specify the prefix to use for the names of newly created threads.
void	setWaitForTasksToCompleteOnShutdown(boolean waitForJobsToCompleteOnShutdown) Set whether to wait for scheduled tasks to complete on shutdown.
void	shutdown() Perform a shutdown on the ThreadPoolExecutor.

Methods inherited from class org.springframework.scheduling.concurrent.CustomizableThreadFactory

newThread

Methods inherited from class org.springframework.util.CustomizableThreadCreator

createThread, getDefaultThreadNamePrefix, getThreadGroup, getThreadNamePrefix, getThreadPriority, isDaemon, nextThreadName, setDaemon, setThreadGroup, setThreadGroupName, setThreadPriority

Methods inherited from class java.lang.Object

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

Field Detail

logger

protected final Log logger

Constructor Detail

ThreadPoolTaskExecutor

public ThreadPoolTaskExecutor()

Method Detail

setCorePoolSize

public void setCorePoolSize(int corePoolSize)

Set the ThreadPoolExecutor's core pool size. Default is 1.

This setting can be modified at runtime, for example through JMX.

getCorePoolSize

public int getCorePoolSize()

Return the ThreadPoolExecutor's core pool size.

setMaxPoolSize

public void setMaxPoolSize(int maxPoolSize)

Set the ThreadPoolExecutor's maximum pool size. Default is Integer.MAX_VALUE.

This setting can be modified at runtime, for example through JMX.

getMaxPoolSize

public int getMaxPoolSize()

Return the ThreadPoolExecutor's maximum pool size.

setKeepAliveSeconds

public void setKeepAliveSeconds(int keepAliveSeconds)

Set the ThreadPoolExecutor's keep-alive seconds. Default is 60.

This setting can be modified at runtime, for example through JMX.

getKeepAliveSeconds

public int getKeepAliveSeconds()

Return the ThreadPoolExecutor's keep-alive seconds.

setAllowCoreThreadTimeOut

public void setAllowCoreThreadTimeOut(boolean allowCoreThreadTimeOut)

Specify whether to allow core threads to time out. This enables dynamic growing and shrinking even in combination with a non-zero queue (since the max pool size will only grow once the queue is full).

Default is "false". Note that this feature is only available on Java 6 or above. On Java 5, consider switching to the backport-concurrent version of ThreadPoolTaskExecutor which also supports this feature.

See Also:

ThreadPoolExecutor.allowCoreThreadTimeOut(boolean)

setQueueCapacity

public void setQueueCapacity(int queueCapacity)

Set the capacity for the ThreadPoolExecutor's BlockingQueue. Default is Integer.MAX_VALUE.

Any positive value will lead to a LinkedBlockingQueue instance; any other value will lead to a SynchronousQueue instance.

See Also:

LinkedBlockingQueue, SynchronousQueue

setThreadFactory

public void setThreadFactory(ThreadFactory threadFactory)

Set the ThreadFactory to use for the ThreadPoolExecutor's thread pool.

Default is this executor itself (i.e. the factory that this executor inherits from). See CustomizableThreadCreator's javadoc for available bean properties.

See Also:

CustomizableThreadCreator.setThreadPriority(int), CustomizableThreadCreator.setDaemon(boolean)

setRejectedExecutionHandler

public void setRejectedExecutionHandler(RejectedExecutionHandler rejectedExecutionHandler)

Set the RejectedExecutionHandler to use for the ThreadPoolExecutor. Default is the ThreadPoolExecutor's default abort policy.

See Also:

ThreadPoolExecutor.AbortPolicy

setWaitForTasksToCompleteOnShutdown

public void setWaitForTasksToCompleteOnShutdown(boolean waitForJobsToCompleteOnShutdown)

Set whether to wait for scheduled tasks to complete on shutdown.

Default is "false". Switch this to "true" if you prefer fully completed tasks at the expense of a longer shutdown phase.

See Also:

ThreadPoolExecutor.shutdown(), ThreadPoolExecutor.shutdownNow()

setThreadNamePrefix

public void setThreadNamePrefix(String threadNamePrefix)

Description copied from class: CustomizableThreadCreator

Specify the prefix to use for the names of newly created threads. Default is "SimpleAsyncTaskExecutor-".

Overrides:

setThreadNamePrefix in class CustomizableThreadCreator

setBeanName

public void setBeanName(String name)

Description copied from interface: BeanNameAware

Set the name of the bean in the bean factory that created this bean.

Invoked after population of normal bean properties but before an init callback such as InitializingBean.afterPropertiesSet() or a custom init-method.

Specified by:

setBeanName in interface BeanNameAware

Parameters:

name - the name of the bean in the factory. Note that this name is the actual bean name used in the factory, which may differ from the originally specified name: in particular for inner bean names, the actual bean name might have been made unique through appending "#..." suffixes. Use the BeanFactoryUtils.originalBeanName(String) method to extract the original bean name (without suffix), if desired.

afterPropertiesSet

public void afterPropertiesSet()

Calls initialize() after the container applied all property values.

Specified by:

afterPropertiesSet in interface InitializingBean

See Also:

initialize()

initialize

public void initialize()

Creates the BlockingQueue and the ThreadPoolExecutor.

See Also:

createQueue(int)

createQueue

protected BlockingQueue createQueue(int queueCapacity)

Create the BlockingQueue to use for the ThreadPoolExecutor.

A LinkedBlockingQueue instance will be created for a positive capacity value; a SynchronousQueue else.

Parameters:

queueCapacity - the specified queue capacity

Returns:

the BlockingQueue instance

See Also:

LinkedBlockingQueue, SynchronousQueue

getThreadPoolExecutor

public ThreadPoolExecutor getThreadPoolExecutor()
                                         throws IllegalStateException

Return the underlying ThreadPoolExecutor for native access.

Returns:

the underlying ThreadPoolExecutor (never null)

Throws:

IllegalStateException - if the ThreadPoolTaskExecutor hasn't been initialized yet

execute

public void execute(Runnable task)

Implementation of both the JDK 1.5 Executor interface and the Spring TaskExecutor interface, delegating to the ThreadPoolExecutor instance.

Specified by:

execute in interface Executor

Specified by:

execute in interface TaskExecutor

Parameters:

task - the Runnable to execute (never null)

See Also:

Executor.execute(Runnable), TaskExecutor.execute(Runnable)

prefersShortLivedTasks

public boolean prefersShortLivedTasks()

This task executor prefers short-lived work units.

Specified by:

prefersShortLivedTasks in interface SchedulingTaskExecutor

Returns:

true if this TaskExecutor prefers short-lived tasks

getPoolSize

public int getPoolSize()

Return the current pool size.

See Also:

ThreadPoolExecutor.getPoolSize()

getActiveCount

public int getActiveCount()

Return the number of currently active threads.

See Also:

ThreadPoolExecutor.getActiveCount()

destroy

public void destroy()

Calls shutdown when the BeanFactory destroys the task executor instance.

Specified by:

destroy in interface DisposableBean

See Also:

shutdown()

shutdown

public void shutdown()

Perform a shutdown on the ThreadPoolExecutor.

See Also:

ThreadPoolExecutor.shutdown()