org.springframework.scheduling.concurrent
Class ThreadPoolTaskScheduler

java.lang.Object
  extended by org.springframework.util.CustomizableThreadCreator
      extended by org.springframework.scheduling.concurrent.CustomizableThreadFactory
          extended by org.springframework.scheduling.concurrent.ExecutorConfigurationSupport
              extended by org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler
All Implemented Interfaces:
Serializable, Executor, ThreadFactory, BeanNameAware, DisposableBean, InitializingBean, AsyncTaskExecutor, TaskExecutor, SchedulingTaskExecutor, TaskScheduler

public class ThreadPoolTaskScheduler
extends ExecutorConfigurationSupport
implements TaskScheduler, SchedulingTaskExecutor

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

Since:
3.0
Author:
Juergen Hoeller, Mark Fisher
See Also:
setPoolSize(int), ExecutorConfigurationSupport.setThreadFactory(java.util.concurrent.ThreadFactory), setErrorHandler(org.springframework.util.ErrorHandler), Serialized Form

Field Summary
 
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
ThreadPoolTaskScheduler()
           
 
Method Summary
protected  ScheduledExecutorService createExecutor(int poolSize, ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler)
          Create a new ScheduledExecutorService instance.
 void execute(Runnable task)
          Execute the given task.
 void execute(Runnable task, long startTimeout)
          Execute the given task.
 ScheduledExecutorService getScheduledExecutor()
          Return the underlying ScheduledExecutorService for native access.
protected  ExecutorService initializeExecutor(ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler)
          Create the target ExecutorService instance.
 boolean prefersShortLivedTasks()
          Does this TaskExecutor prefer short-lived tasks over long-lived tasks?
 ScheduledFuture schedule(Runnable task, Date startTime)
          Schedule the given Runnable, invoking it at the specified execution time.
 ScheduledFuture schedule(Runnable task, Trigger trigger)
          Schedule the given Runnable, invoking it whenever the trigger indicates a next execution time.
 ScheduledFuture scheduleAtFixedRate(Runnable task, Date startTime, long period)
          Schedule the given Runnable, invoking it at the specified execution time and subsequently with the given period.
 ScheduledFuture scheduleAtFixedRate(Runnable task, long period)
          Schedule the given Runnable, starting as soon as possible and invoking it with the given period.
 ScheduledFuture scheduleWithFixedDelay(Runnable task, 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.
 ScheduledFuture scheduleWithFixedDelay(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)
          Provide an ErrorHandler strategy.
 void setPoolSize(int poolSize)
          Set the ScheduledExecutorService's pool size.
<T> Future<T>
submit(Callable<T> task)
          Submit a Callable task for execution, receiving a Future representing that task.
 Future<?> submit(Runnable task)
          Submit a Runnable task for execution, receiving a Future representing that task.
 
Methods inherited from class org.springframework.scheduling.concurrent.ExecutorConfigurationSupport
afterPropertiesSet, destroy, initialize, 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
 

Constructor Detail

ThreadPoolTaskScheduler

public ThreadPoolTaskScheduler()
Method Detail

setPoolSize

public void setPoolSize(int poolSize)
Set the ScheduledExecutorService's pool size. Default is 1.


setErrorHandler

public void setErrorHandler(ErrorHandler errorHandler)
Provide an ErrorHandler strategy.


initializeExecutor

protected ExecutorService initializeExecutor(ThreadFactory threadFactory,
                                             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 ScheduledExecutorService createExecutor(int poolSize,
                                                  ThreadFactory threadFactory,
                                                  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 ScheduledExecutorService getScheduledExecutor()
                                              throws IllegalStateException
Return the underlying ScheduledExecutorService for native access.

Returns:
the underlying ScheduledExecutorService (never null)
Throws:
IllegalStateException - if the ThreadPoolTaskScheduler hasn't been initialized yet

execute

public void execute(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 Executor
Specified by:
execute in interface TaskExecutor
Parameters:
task - the Runnable to execute (never null)

execute

public void execute(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 Future<?> submit(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> Future<T> submit(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

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 ScheduledFuture schedule(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 ScheduledFuture schedule(Runnable task,
                                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
Returns:
a ScheduledFuture representing pending completion of the task

scheduleAtFixedRate

public ScheduledFuture scheduleAtFixedRate(Runnable task,
                                           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
period - the interval between successive executions of the task
Returns:
a ScheduledFuture representing pending completion of the task

scheduleAtFixedRate

public ScheduledFuture scheduleAtFixedRate(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
Returns:
a ScheduledFuture representing pending completion of the task

scheduleWithFixedDelay

public ScheduledFuture scheduleWithFixedDelay(Runnable task,
                                              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
delay - the delay between the completion of one execution and the start of the next
Returns:
a ScheduledFuture representing pending completion of the task

scheduleWithFixedDelay

public ScheduledFuture scheduleWithFixedDelay(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
Returns:
a ScheduledFuture representing pending completion of the task