org.springframework.scheduling

Interface TaskScheduler

All Known Implementing Classes:

ConcurrentTaskScheduler, ThreadPoolTaskScheduler

public interface TaskScheduler

Task scheduler interface that abstracts the scheduling of Runnables based on different kinds of triggers.

This interface is separate from SchedulingTaskExecutor since it usually represents for a different kind of backend, i.e. a thread pool with different characteristics and capabilities. Implementations may implement both interfaces if they can handle both kinds of execution characteristics.

The 'default' implementation is ThreadPoolTaskScheduler, wrapping a native ScheduledExecutorService and adding extended trigger capabilities.

This interface is roughly equivalent to a JSR-236 ManagedScheduledExecutorService as supported in Java EE 6 environments. However, at the time of the Spring 3.0 release, the JSR-236 interfaces have not been released in official form yet.

Since:

3.0

Author:

Juergen Hoeller

See Also:

TaskExecutor, ScheduledExecutorService, ThreadPoolTaskScheduler

Method Summary

Methods

Modifier and Type	Method and Description
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.

Method Detail

schedule

ScheduledFuture schedule(Runnable task,
                       Trigger trigger)

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.

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))

Throws:

org.springframework.core.task.TaskRejectedException - if the given task was not accepted for internal reasons (e.g. a pool overload handling policy or a pool shutdown in progress)

See Also:

CronTrigger

schedule

ScheduledFuture schedule(Runnable task,
                       Date startTime)

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.

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

Throws:

org.springframework.core.task.TaskRejectedException - if the given task was not accepted for internal reasons (e.g. a pool overload handling policy or a pool shutdown in progress)

scheduleAtFixedRate

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.

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

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

Throws:

org.springframework.core.task.TaskRejectedException - if the given task was not accepted for internal reasons (e.g. a pool overload handling policy or a pool shutdown in progress)

scheduleAtFixedRate

ScheduledFuture scheduleAtFixedRate(Runnable task,
                                  long period)

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.

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

Throws:

org.springframework.core.task.TaskRejectedException - if the given task was not accepted for internal reasons (e.g. a pool overload handling policy or a pool shutdown in progress)

scheduleWithFixedDelay

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.

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

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

Throws:

org.springframework.core.task.TaskRejectedException - if the given task was not accepted for internal reasons (e.g. a pool overload handling policy or a pool shutdown in progress)

scheduleWithFixedDelay

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.

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

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

Throws:

org.springframework.core.task.TaskRejectedException - if the given task was not accepted for internal reasons (e.g. a pool overload handling policy or a pool shutdown in progress)