public class ScheduledExecutorFactoryBean extends ExecutorConfigurationSupport implements FactoryBean<ScheduledExecutorService>
FactoryBeanthat sets up a
ScheduledExecutorService(by default: a
ScheduledThreadPoolExecutor) and exposes it for bean references.
Allows for registration of
automatically starting the
ScheduledExecutorService on initialization and
cancelling it on destruction of the context. In scenarios that only require static
registration of tasks at startup, there is no need to access the
ScheduledExecutorService instance itself in application code at all;
ScheduledExecutorFactoryBean is then just being used for lifecycle integration.
For an alternative, you may set up a
directly using constructor injection, or use a factory method definition that points
This is strongly recommended in particular for common
@Bean methods in
configuration classes, where this
FactoryBean variant would force you to
FactoryBean type instead of
Runnables submitted via a native
ScheduledExecutorService are removed from
the execution schedule once they throw an exception. If you would prefer
to continue execution after such an exception, switch this FactoryBean's
property to "true".
|Constructor and Description|
|Modifier and Type||Method and Description|
Create a new
Return an instance (possibly shared or independent) of the object managed by this factory.
Return the type of object that this FactoryBean creates, or
Determine the actual Runnable to schedule for the given task.
Create the target
Is the object managed by this factory a singleton? That is, will
Specify whether to continue the execution of a scheduled task after it threw an exception.
Specify whether this FactoryBean should expose an unconfigurable decorator for the created executor.
Set the ScheduledExecutorService's pool size.
Set the remove-on-cancel mode on
Register a list of ScheduledExecutorTask objects with the ScheduledExecutorService that this FactoryBean creates.
afterPropertiesSet, destroy, initialize, setAwaitTerminationSeconds, setBeanName, setRejectedExecutionHandler, setThreadFactory, setThreadNamePrefix, setWaitForTasksToCompleteOnShutdown, shutdown
createThread, getDefaultThreadNamePrefix, getThreadGroup, getThreadNamePrefix, getThreadPriority, isDaemon, nextThreadName, setDaemon, setThreadGroup, setThreadGroupName, setThreadPriority
public void setPoolSize(int poolSize)
public void setScheduledExecutorTasks(ScheduledExecutorTask... scheduledExecutorTasks)
ScheduledExecutorService.schedule(java.lang.Runnable, long, java.util.concurrent.TimeUnit),
ScheduledExecutorService.scheduleWithFixedDelay(java.lang.Runnable, long, long, java.util.concurrent.TimeUnit),
ScheduledExecutorService.scheduleAtFixedRate(java.lang.Runnable, long, long, java.util.concurrent.TimeUnit)
public void setRemoveOnCancelPolicy(boolean removeOnCancelPolicy)
false. If set to
true, the target executor will be
switched into remove-on-cancel mode (if possible, with a soft fallback otherwise).
public void setContinueScheduledExecutionAfterException(boolean continueScheduledExecutionAfterException)
Default is "false", matching the native behavior of a
Switch this flag to "true" for exception-proof execution of each task,
continuing scheduled execution as in the case of successful execution.
public void setExposeUnconfigurableExecutor(boolean exposeUnconfigurableExecutor)
Default is "false", exposing the raw executor as bean reference. Switch this flag to "true" to strictly prevent clients from modifying the executor's configuration.
protected ExecutorService initializeExecutor(ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler)
ExecutorServiceinstance. Called by
protected ScheduledExecutorService createExecutor(int poolSize, ThreadFactory threadFactory, RejectedExecutionHandler rejectedExecutionHandler)
protected void registerTasks(ScheduledExecutorTask tasks, ScheduledExecutorService executor)
tasks- the specified ScheduledExecutorTasks (never empty)
executor- the ScheduledExecutorService to register the tasks on.
protected Runnable getRunnableToSchedule(ScheduledExecutorTask task)
Wraps the task's Runnable in a
that will catch and log the Exception. If necessary, it will suppress the
Exception according to the
task- the ScheduledExecutorTask to schedule
public ScheduledExecutorService getObject()
As with a
BeanFactory, this allows support for both the
Singleton and Prototype design pattern.
If this FactoryBean is not fully initialized yet at the time of
the call (for example because it is involved in a circular reference),
throw a corresponding
As of Spring 2.0, FactoryBeans are allowed to return
objects. The factory will consider this as normal value to be used; it
will not throw a FactoryBeanNotInitializedException in this case anymore.
FactoryBean implementations are encouraged to throw
FactoryBeanNotInitializedException themselves now, as appropriate.
public Class<? extends ScheduledExecutorService> getObjectType()
nullif not known in advance.
This allows one to check for specific types of beans without instantiating objects, for example on autowiring.
In the case of implementations that are creating a singleton object, this method should try to avoid singleton creation as far as possible; it should rather estimate the type in advance. For prototypes, returning a meaningful type here is advisable too.
This method can be called before this FactoryBean has been fully initialized. It must not rely on state created during initialization; of course, it can still use such state if available.
NOTE: Autowiring will simply ignore FactoryBeans that return
null here. Therefore it is highly recommended to implement
this method properly, using the current state of the FactoryBean.
nullif not known at the time of the call
public boolean isSingleton()
FactoryBean.getObject()always return the same object (a reference that can be cached)?
NOTE: If a FactoryBean indicates to hold a singleton object,
the object returned from
getObject() might get cached
by the owning BeanFactory. Hence, do not return
unless the FactoryBean always exposes the same reference.
The singleton status of the FactoryBean itself will generally be provided by the owning BeanFactory; usually, it has to be defined as singleton there.
NOTE: This method returning
false does not
necessarily indicate that returned objects are independent instances.
An implementation of the extended
may explicitly indicate independent instances through its
SmartFactoryBean.isPrototype() method. Plain
implementations which do not implement this extended interface are
simply assumed to always return independent instances if the
isSingleton() implementation returns
The default implementation returns
true, since a
FactoryBean typically manages a singleton instance.