org.springframework.scheduling.concurrent

Class ThreadPoolTaskScheduler

java.lang.Object

org.springframework.util.CustomizableThreadCreator

org.springframework.scheduling.concurrent.CustomizableThreadFactory

org.springframework.scheduling.concurrent.ExecutorConfigurationSupport

org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler

All Implemented Interfaces:

java.io.Serializable, java.util.concurrent.Executor, java.util.concurrent.ThreadFactory, Aware, BeanNameAware, DisposableBean, InitializingBean, AsyncListenableTaskExecutor, AsyncTaskExecutor, TaskExecutor, SchedulingTaskExecutor, TaskScheduler

public class ThreadPoolTaskScheduler
extends ExecutorConfigurationSupport
implements AsyncListenableTaskExecutor, SchedulingTaskExecutor, TaskScheduler

Implementation of Spring's TaskScheduler interface, wrapping a native ScheduledThreadPoolExecutor.

Since:

3.0

Author:

Juergen Hoeller, Mark Fisher

See Also:

setPoolSize(int), setRemoveOnCancelPolicy(boolean), ExecutorConfigurationSupport.setThreadFactory(java.util.concurrent.ThreadFactory), setErrorHandler(org.springframework.util.ErrorHandler), Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	ThreadPoolTaskScheduler.DelegatingErrorHandlingCallable<V>

Field Summary

Fields

Modifier and Type	Field and Description
private ErrorHandler	errorHandler
private int	poolSize
private boolean	removeOnCancelPolicy
private java.util.concurrent.ScheduledExecutorService	scheduledExecutor
private static boolean	setRemoveOnCancelPolicyAvailable

Fields inherited from class org.springframework.scheduling.concurrent.ExecutorConfigurationSupport

logger

Fields inherited from interface org.springframework.core.task.AsyncTaskExecutor

TIMEOUT_IMMEDIATE, TIMEOUT_INDEFINITE

Constructor Summary

Constructors

Constructor and Description
ThreadPoolTaskScheduler()

Method Summary

Modifier and Type	Method and Description
protected java.util.concurrent.ScheduledExecutorService	createExecutor(int poolSize, java.util.concurrent.ThreadFactory threadFactory, java.util.concurrent.RejectedExecutionHandler rejectedExecutionHandler) Create a new ScheduledExecutorService instance.
private java.lang.Runnable	errorHandlingTask(java.lang.Runnable task, boolean isRepeatingTask)
void	execute(java.lang.Runnable task) Execute the given task.
void	execute(java.lang.Runnable task, long startTimeout) Execute the given task.
int	getActiveCount() Return the number of currently active threads.
int	getPoolSize() Return the current pool size.
java.util.concurrent.ScheduledExecutorService	getScheduledExecutor() Return the underlying ScheduledExecutorService for native access.
java.util.concurrent.ScheduledThreadPoolExecutor	getScheduledThreadPoolExecutor() Return the underlying ScheduledThreadPoolExecutor, if available.
protected java.util.concurrent.ExecutorService	initializeExecutor(java.util.concurrent.ThreadFactory threadFactory, java.util.concurrent.RejectedExecutionHandler rejectedExecutionHandler) Create the target ExecutorService instance.
boolean	isRemoveOnCancelPolicy() Return the current setting for the remove-on-cancel mode.
boolean	prefersShortLivedTasks() Does this TaskExecutor prefer short-lived tasks over long-lived tasks?
java.util.concurrent.ScheduledFuture<?>	schedule(java.lang.Runnable task, java.util.Date startTime) Schedule the given Runnable, invoking it at the specified execution time.
java.util.concurrent.ScheduledFuture<?>	schedule(java.lang.Runnable task, Trigger trigger) Schedule the given Runnable, invoking it whenever the trigger indicates a next execution time.
java.util.concurrent.ScheduledFuture<?>	scheduleAtFixedRate(java.lang.Runnable task, java.util.Date startTime, long period) Schedule the given Runnable, invoking it at the specified execution time and subsequently with the given period.
java.util.concurrent.ScheduledFuture<?>	scheduleAtFixedRate(java.lang.Runnable task, long period) Schedule the given Runnable, starting as soon as possible and invoking it with the given period.
java.util.concurrent.ScheduledFuture<?>	scheduleWithFixedDelay(java.lang.Runnable task, java.util.Date startTime, long delay) Schedule the given Runnable, invoking it at the specified execution time and subsequently with the given delay between the completion of one execution and the start of the next.
java.util.concurrent.ScheduledFuture<?>	scheduleWithFixedDelay(java.lang.Runnable task, long delay) Schedule the given Runnable, starting as soon as possible and invoking it with the given delay between the completion of one execution and the start of the next.
void	setErrorHandler(ErrorHandler errorHandler) Set a custom ErrorHandler strategy.
void	setPoolSize(int poolSize) Set the ScheduledExecutorService's pool size.
void	setRemoveOnCancelPolicy(boolean removeOnCancelPolicy) Set the remove-on-cancel mode on ScheduledThreadPoolExecutor (JDK 7+).
<T> java.util.concurrent.Future<T>	submit(java.util.concurrent.Callable<T> task) Submit a Callable task for execution, receiving a Future representing that task.
java.util.concurrent.Future<?>	submit(java.lang.Runnable task) Submit a Runnable task for execution, receiving a Future representing that task.
<T> ListenableFuture<T>	submitListenable(java.util.concurrent.Callable<T> task) Submit a Callable task for execution, receiving a ListenableFuture representing that task.
ListenableFuture<?>	submitListenable(java.lang.Runnable task) Submit a Runnable task for execution, receiving a ListenableFuture representing that task.

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

afterPropertiesSet, destroy, initialize, setAwaitTerminationSeconds, setBeanName, setRejectedExecutionHandler, setThreadFactory, setThreadNamePrefix, setWaitForTasksToCompleteOnShutdown, shutdown

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

setRemoveOnCancelPolicyAvailable

private static final boolean setRemoveOnCancelPolicyAvailable

poolSize

private volatile int poolSize

removeOnCancelPolicy

private volatile boolean removeOnCancelPolicy

scheduledExecutor

private volatile java.util.concurrent.ScheduledExecutorService scheduledExecutor

errorHandler

private volatile ErrorHandler errorHandler

Constructor Detail

ThreadPoolTaskScheduler

public ThreadPoolTaskScheduler()

Method Detail

setPoolSize

public void setPoolSize(int poolSize)

Set the ScheduledExecutorService's pool size. Default is 1.

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

setRemoveOnCancelPolicy

@UsesJava7
public void setRemoveOnCancelPolicy(boolean removeOnCancelPolicy)

Set the remove-on-cancel mode on ScheduledThreadPoolExecutor (JDK 7+).

Default is false. If set to true, the target executor will be switched into remove-on-cancel mode (if possible, with a soft fallback otherwise).

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

setErrorHandler

public void setErrorHandler(ErrorHandler errorHandler)

Set a custom ErrorHandler strategy.

initializeExecutor

@UsesJava7
protected java.util.concurrent.ExecutorService initializeExecutor(java.util.concurrent.ThreadFactory threadFactory,
                                                                             java.util.concurrent.RejectedExecutionHandler rejectedExecutionHandler)

Description copied from class: ExecutorConfigurationSupport

Create the target ExecutorService instance. Called by afterPropertiesSet.

Specified by:

initializeExecutor in class ExecutorConfigurationSupport

Parameters:

threadFactory - the ThreadFactory to use

rejectedExecutionHandler - the RejectedExecutionHandler to use

Returns:

a new ExecutorService instance

See Also:

ExecutorConfigurationSupport.afterPropertiesSet()

createExecutor

protected java.util.concurrent.ScheduledExecutorService createExecutor(int poolSize,
                                                                       java.util.concurrent.ThreadFactory threadFactory,
                                                                       java.util.concurrent.RejectedExecutionHandler rejectedExecutionHandler)

Create a new ScheduledExecutorService instance.

The default implementation creates a ScheduledThreadPoolExecutor. Can be overridden in subclasses to provide custom ScheduledExecutorService instances.

Parameters:

poolSize - the specified pool size

threadFactory - the ThreadFactory to use

rejectedExecutionHandler - the RejectedExecutionHandler to use

Returns:

a new ScheduledExecutorService instance

See Also:

ExecutorConfigurationSupport.afterPropertiesSet(), ScheduledThreadPoolExecutor

getScheduledExecutor

public java.util.concurrent.ScheduledExecutorService getScheduledExecutor()
                                                                   throws java.lang.IllegalStateException

Return the underlying ScheduledExecutorService for native access.

Returns:

the underlying ScheduledExecutorService (never null)

Throws:

java.lang.IllegalStateException - if the ThreadPoolTaskScheduler hasn't been initialized yet

getScheduledThreadPoolExecutor

public java.util.concurrent.ScheduledThreadPoolExecutor getScheduledThreadPoolExecutor()
                                                                                throws java.lang.IllegalStateException

Return the underlying ScheduledThreadPoolExecutor, if available.

Returns:

the underlying ScheduledExecutorService (never null)

Throws:

java.lang.IllegalStateException - if the ThreadPoolTaskScheduler hasn't been initialized yet or if the underlying ScheduledExecutorService isn't a ScheduledThreadPoolExecutor

See Also:

getScheduledExecutor()

getPoolSize

public int getPoolSize()

Return the current pool size.

Requires an underlying ScheduledThreadPoolExecutor.

See Also:

getScheduledThreadPoolExecutor(), ThreadPoolExecutor.getPoolSize()

isRemoveOnCancelPolicy

@UsesJava7
public boolean isRemoveOnCancelPolicy()

Return the current setting for the remove-on-cancel mode.

Requires an underlying ScheduledThreadPoolExecutor.

getActiveCount

public int getActiveCount()

Return the number of currently active threads.

Requires an underlying ScheduledThreadPoolExecutor.

See Also:

getScheduledThreadPoolExecutor(), ThreadPoolExecutor.getActiveCount()

execute

public void execute(java.lang.Runnable task)

Description copied from interface: TaskExecutor

Execute the given task.

The call might return immediately if the implementation uses an asynchronous execution strategy, or might block in the case of synchronous execution.

Specified by:

execute in interface java.util.concurrent.Executor

Specified by:

execute in interface TaskExecutor

Parameters:

task - the Runnable to execute (never null)

execute

public void execute(java.lang.Runnable task,
                    long startTimeout)

Description copied from interface: AsyncTaskExecutor

Execute the given task.

Specified by:

execute in interface AsyncTaskExecutor

Parameters:

task - the Runnable to execute (never null)

startTimeout - the time duration (milliseconds) within which the task is supposed to start. This is intended as a hint to the executor, allowing for preferred handling of immediate tasks. Typical values are AsyncTaskExecutor.TIMEOUT_IMMEDIATE or AsyncTaskExecutor.TIMEOUT_INDEFINITE (the default as used by TaskExecutor.execute(Runnable)).

submit

public java.util.concurrent.Future<?> submit(java.lang.Runnable task)

Description copied from interface: AsyncTaskExecutor

Submit a Runnable task for execution, receiving a Future representing that task. The Future will return a null result upon completion.

Specified by:

submit in interface AsyncTaskExecutor

Parameters:

task - the Runnable to execute (never null)

Returns:

a Future representing pending completion of the task

submit

public <T> java.util.concurrent.Future<T> submit(java.util.concurrent.Callable<T> task)

Description copied from interface: AsyncTaskExecutor

Submit a Callable task for execution, receiving a Future representing that task. The Future will return the Callable's result upon completion.

Specified by:

submit in interface AsyncTaskExecutor

Parameters:

task - the Callable to execute (never null)

Returns:

a Future representing pending completion of the task

submitListenable

public ListenableFuture<?> submitListenable(java.lang.Runnable task)

Description copied from interface: AsyncListenableTaskExecutor

Submit a Runnable task for execution, receiving a ListenableFuture representing that task. The Future will return a null result upon completion.

Specified by:

submitListenable in interface AsyncListenableTaskExecutor

Parameters:

task - the Runnable to execute (never null)

Returns:

a ListenableFuture representing pending completion of the task

submitListenable

public <T> ListenableFuture<T> submitListenable(java.util.concurrent.Callable<T> task)

Description copied from interface: AsyncListenableTaskExecutor

Submit a Callable task for execution, receiving a ListenableFuture representing that task. The Future will return the Callable's result upon completion.

Specified by:

submitListenable in interface AsyncListenableTaskExecutor

Parameters:

task - the Callable to execute (never null)

Returns:

a ListenableFuture representing pending completion of the task

prefersShortLivedTasks

public boolean prefersShortLivedTasks()

Description copied from interface: SchedulingTaskExecutor

Does this TaskExecutor prefer short-lived tasks over long-lived tasks?

A SchedulingTaskExecutor implementation can indicate whether it prefers submitted tasks to perform as little work as they can within a single task execution. For example, submitted tasks might break a repeated loop into individual subtasks which submit a follow-up task afterwards (if feasible).

This should be considered a hint. Of course TaskExecutor clients are free to ignore this flag and hence the SchedulingTaskExecutor interface overall. However, thread pools will usually indicated a preference for short-lived tasks, to be able to perform more fine-grained scheduling.

Specified by:

prefersShortLivedTasks in interface SchedulingTaskExecutor

Returns:

true if this TaskExecutor prefers short-lived tasks

schedule

public java.util.concurrent.ScheduledFuture<?> schedule(java.lang.Runnable task,
                                                        Trigger trigger)

Description copied from interface: TaskScheduler

Schedule the given Runnable, invoking it whenever the trigger indicates a next execution time.

Execution will end once the scheduler shuts down or the returned ScheduledFuture gets cancelled.

Specified by:

schedule in interface TaskScheduler

Parameters:

task - the Runnable to execute whenever the trigger fires

trigger - an implementation of the Trigger interface, e.g. a CronTrigger object wrapping a cron expression

Returns:

a ScheduledFuture representing pending completion of the task, or null if the given Trigger object never fires (i.e. returns null from Trigger.nextExecutionTime(org.springframework.scheduling.TriggerContext))

See Also:

CronTrigger

schedule

public java.util.concurrent.ScheduledFuture<?> schedule(java.lang.Runnable task,
                                                        java.util.Date startTime)

Description copied from interface: TaskScheduler

Schedule the given Runnable, invoking it at the specified execution time.

Execution will end once the scheduler shuts down or the returned ScheduledFuture gets cancelled.

Specified by:

schedule in interface TaskScheduler

Parameters:

task - the Runnable to execute whenever the trigger fires

startTime - the desired execution time for the task (if this is in the past, the task will be executed immediately, i.e. as soon as possible)

Returns:

a ScheduledFuture representing pending completion of the task

scheduleAtFixedRate

public java.util.concurrent.ScheduledFuture<?> scheduleAtFixedRate(java.lang.Runnable task,
                                                                   java.util.Date startTime,
                                                                   long period)

Description copied from interface: TaskScheduler

Schedule the given Runnable, invoking it at the specified execution time and subsequently with the given period.

Execution will end once the scheduler shuts down or the returned ScheduledFuture gets cancelled.

Specified by:

scheduleAtFixedRate in interface TaskScheduler

Parameters:

task - the Runnable to execute whenever the trigger fires

startTime - the desired first execution time for the task (if this is in the past, the task will be executed immediately, i.e. as soon as possible)

period - the interval between successive executions of the task (in milliseconds)

Returns:

a ScheduledFuture representing pending completion of the task

scheduleAtFixedRate

public java.util.concurrent.ScheduledFuture<?> scheduleAtFixedRate(java.lang.Runnable task,
                                                                   long period)

Description copied from interface: TaskScheduler

Schedule the given Runnable, starting as soon as possible and invoking it with the given period.

Execution will end once the scheduler shuts down or the returned ScheduledFuture gets cancelled.

Specified by:

scheduleAtFixedRate in interface TaskScheduler

Parameters:

task - the Runnable to execute whenever the trigger fires

period - the interval between successive executions of the task (in milliseconds)

Returns:

a ScheduledFuture representing pending completion of the task

scheduleWithFixedDelay

public java.util.concurrent.ScheduledFuture<?> scheduleWithFixedDelay(java.lang.Runnable task,
                                                                      java.util.Date startTime,
                                                                      long delay)

Description copied from interface: TaskScheduler

Schedule the given Runnable, invoking it at the specified execution time and subsequently with the given delay between the completion of one execution and the start of the next.

Execution will end once the scheduler shuts down or the returned ScheduledFuture gets cancelled.

Specified by:

scheduleWithFixedDelay in interface TaskScheduler

Parameters:

task - the Runnable to execute whenever the trigger fires

startTime - the desired first execution time for the task (if this is in the past, the task will be executed immediately, i.e. as soon as possible)

delay - the delay between the completion of one execution and the start of the next (in milliseconds)

Returns:

a ScheduledFuture representing pending completion of the task

scheduleWithFixedDelay

public java.util.concurrent.ScheduledFuture<?> scheduleWithFixedDelay(java.lang.Runnable task,
                                                                      long delay)

Description copied from interface: TaskScheduler

Schedule the given Runnable, starting as soon as possible and invoking it with the given delay between the completion of one execution and the start of the next.

Execution will end once the scheduler shuts down or the returned ScheduledFuture gets cancelled.

Specified by:

scheduleWithFixedDelay in interface TaskScheduler

Parameters:

task - the Runnable to execute whenever the trigger fires

delay - the interval between successive executions of the task (in milliseconds)

Returns:

a ScheduledFuture representing pending completion of the task

errorHandlingTask

private java.lang.Runnable errorHandlingTask(java.lang.Runnable task,
                                             boolean isRepeatingTask)