public class ScheduledExecutorFactoryBean extends ExecutorConfigurationSupport implements FactoryBean<java.util.concurrent.ScheduledExecutorService>
FactoryBean
that sets up
a ScheduledExecutorService
(by default: a ScheduledThreadPoolExecutor
)
and exposes it for bean references.
Allows for registration of ScheduledExecutorTasks
,
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 ScheduledThreadPoolExecutor
instance
directly using constructor injection, or use a factory method definition that points
to the Executors
class.
This is strongly recommended in particular for common @Bean
methods in
configuration classes, where this FactoryBean
variant would force you to
return the FactoryBean
type instead of ScheduledExecutorService
.
Note that ScheduledExecutorService
uses a Runnable
instance that is shared between repeated executions,
in contrast to Quartz which instantiates a new Job for each execution.
WARNING: 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
"continueScheduledExecutionAfterException"
property to "true".
setPoolSize(int)
,
setRemoveOnCancelPolicy(boolean)
,
ExecutorConfigurationSupport.setThreadFactory(java.util.concurrent.ThreadFactory)
,
ScheduledExecutorTask
,
ScheduledExecutorService
,
ScheduledThreadPoolExecutor
,
Serialized Formlogger
Constructor and Description |
---|
ScheduledExecutorFactoryBean() |
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. |
java.util.concurrent.ScheduledExecutorService |
getObject()
Return an instance (possibly shared or independent) of the object
managed by this factory.
|
java.lang.Class<? extends java.util.concurrent.ScheduledExecutorService> |
getObjectType()
Return the type of object that this FactoryBean creates,
or
null if not known in advance. |
protected java.lang.Runnable |
getRunnableToSchedule(ScheduledExecutorTask task)
Determine the actual Runnable to schedule for the given task.
|
protected java.util.concurrent.ExecutorService |
initializeExecutor(java.util.concurrent.ThreadFactory threadFactory,
java.util.concurrent.RejectedExecutionHandler rejectedExecutionHandler)
Create the target
ExecutorService instance. |
boolean |
isSingleton()
Is the object managed by this factory a singleton? That is,
will
FactoryBean.getObject() always return the same object
(a reference that can be cached)? |
protected void |
registerTasks(ScheduledExecutorTask[] tasks,
java.util.concurrent.ScheduledExecutorService executor)
Register the specified
ScheduledExecutorTasks
on the given ScheduledExecutorService . |
void |
setContinueScheduledExecutionAfterException(boolean continueScheduledExecutionAfterException)
Specify whether to continue the execution of a scheduled task
after it threw an exception.
|
void |
setExposeUnconfigurableExecutor(boolean exposeUnconfigurableExecutor)
Specify whether this FactoryBean should expose an unconfigurable
decorator for the created executor.
|
void |
setPoolSize(int poolSize)
Set the ScheduledExecutorService's pool size.
|
void |
setRemoveOnCancelPolicy(boolean removeOnCancelPolicy)
Set the remove-on-cancel mode on
ScheduledThreadPoolExecutor (JDK 7+). |
void |
setScheduledExecutorTasks(ScheduledExecutorTask... scheduledExecutorTasks)
Register a list of ScheduledExecutorTask objects with the ScheduledExecutorService
that this FactoryBean creates.
|
afterPropertiesSet, cancelRemainingTask, destroy, initialize, setAwaitTerminationSeconds, setBeanName, setRejectedExecutionHandler, setThreadFactory, setThreadNamePrefix, setWaitForTasksToCompleteOnShutdown, shutdown
newThread
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)
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).
public void setContinueScheduledExecutionAfterException(boolean continueScheduledExecutionAfterException)
Default is "false", matching the native behavior of a
ScheduledExecutorService
.
Switch this flag to "true" for exception-proof execution of each task,
continuing scheduled execution as in the case of successful execution.
ScheduledExecutorService.scheduleAtFixedRate(java.lang.Runnable, long, long, java.util.concurrent.TimeUnit)
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.
Executors.unconfigurableScheduledExecutorService(java.util.concurrent.ScheduledExecutorService)
protected java.util.concurrent.ExecutorService initializeExecutor(java.util.concurrent.ThreadFactory threadFactory, java.util.concurrent.RejectedExecutionHandler rejectedExecutionHandler)
ExecutorConfigurationSupport
ExecutorService
instance.
Called by afterPropertiesSet
.initializeExecutor
in class ExecutorConfigurationSupport
threadFactory
- the ThreadFactory to userejectedExecutionHandler
- the RejectedExecutionHandler to useExecutorConfigurationSupport.afterPropertiesSet()
protected java.util.concurrent.ScheduledExecutorService createExecutor(int poolSize, java.util.concurrent.ThreadFactory threadFactory, java.util.concurrent.RejectedExecutionHandler rejectedExecutionHandler)
ScheduledExecutorService
instance.
The default implementation creates a ScheduledThreadPoolExecutor
.
Can be overridden in subclasses to provide custom ScheduledExecutorService
instances.
poolSize
- the specified pool sizethreadFactory
- the ThreadFactory to userejectedExecutionHandler
- the RejectedExecutionHandler to useExecutorConfigurationSupport.afterPropertiesSet()
,
ScheduledThreadPoolExecutor
protected void registerTasks(ScheduledExecutorTask[] tasks, java.util.concurrent.ScheduledExecutorService executor)
ScheduledExecutorTasks
on the given ScheduledExecutorService
.tasks
- the specified ScheduledExecutorTasks (never empty)executor
- the ScheduledExecutorService to register the tasks on.protected java.lang.Runnable getRunnableToSchedule(ScheduledExecutorTask task)
Wraps the task's Runnable in a
DelegatingErrorHandlingRunnable
that will catch and log the Exception. If necessary, it will suppress the
Exception according to the
"continueScheduledExecutionAfterException"
flag.
task
- the ScheduledExecutorTask to schedule@Nullable public java.util.concurrent.ScheduledExecutorService getObject()
FactoryBean
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 FactoryBeanNotInitializedException
.
As of Spring 2.0, FactoryBeans are allowed to return null
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.
getObject
in interface FactoryBean<java.util.concurrent.ScheduledExecutorService>
null
)FactoryBeanNotInitializedException
public java.lang.Class<? extends java.util.concurrent.ScheduledExecutorService> getObjectType()
FactoryBean
null
if 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.
getObjectType
in interface FactoryBean<java.util.concurrent.ScheduledExecutorService>
null
if not known at the time of the callListableBeanFactory.getBeansOfType(java.lang.Class<T>)
public boolean isSingleton()
FactoryBean
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 true
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 SmartFactoryBean
interface
may explicitly indicate independent instances through its
SmartFactoryBean.isPrototype()
method. Plain FactoryBean
implementations which do not implement this extended interface are
simply assumed to always return independent instances if the
isSingleton()
implementation returns false
.
The default implementation returns true
, since a
FactoryBean
typically manages a singleton instance.
isSingleton
in interface FactoryBean<java.util.concurrent.ScheduledExecutorService>
FactoryBean.getObject()
,
SmartFactoryBean.isPrototype()