@UsesJava7 public class ForkJoinPoolFactoryBean extends Object implements FactoryBean<ForkJoinPool>, InitializingBean, DisposableBean
FactoryBean
that builds and exposes a preconfigured ForkJoinPool
.
May be used on Java 7 and 8 as well as on Java 6 with jsr166.jar
on the classpath
(ideally on the VM bootstrap classpath).
For details on the ForkJoinPool API and its use with RecursiveActions, see the JDK 7 javadoc.
jsr166.jar
, containing java.util.concurrent
updates for Java 6, can be obtained
from the concurrency interest website.
Constructor and Description |
---|
ForkJoinPoolFactoryBean() |
Modifier and Type | Method and Description |
---|---|
void |
afterPropertiesSet()
Invoked by the containing
BeanFactory after it has set all bean properties
and satisfied BeanFactoryAware , ApplicationContextAware etc. |
void |
destroy()
Invoked by the containing
BeanFactory on destruction of a bean. |
ForkJoinPool |
getObject()
Return an instance (possibly shared or independent) of the object
managed by this factory.
|
Class<?> |
getObjectType()
Return the type of object that this FactoryBean creates,
or
null if not known in advance. |
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)? |
void |
setAsyncMode(boolean asyncMode)
Specify whether to establish a local first-in-first-out scheduling mode for forked tasks
that are never joined.
|
void |
setAwaitTerminationSeconds(int awaitTerminationSeconds)
Set the maximum number of seconds that this ForkJoinPool is supposed to block
on shutdown in order to wait for remaining tasks to complete their execution
before the rest of the container continues to shut down.
|
void |
setCommonPool(boolean commonPool)
Set whether to expose JDK 8's 'common'
ForkJoinPool . |
void |
setParallelism(int parallelism)
Specify the parallelism level.
|
void |
setThreadFactory(ForkJoinPool.ForkJoinWorkerThreadFactory threadFactory)
Set the factory for creating new ForkJoinWorkerThreads.
|
void |
setUncaughtExceptionHandler(Thread.UncaughtExceptionHandler uncaughtExceptionHandler)
Set the handler for internal worker threads that terminate due to unrecoverable errors
encountered while executing tasks.
|
public void setCommonPool(boolean commonPool)
ForkJoinPool
.
Default is "false", creating a local ForkJoinPool
instance based on the
"parallelism"
, "threadFactory"
,
"uncaughtExceptionHandler"
and
"asyncMode"
properties on this FactoryBean.
NOTE: Setting this flag to "true" effectively ignores all other
properties on this FactoryBean, reusing the shared common JDK ForkJoinPool
instead. This is a fine choice on JDK 8 but does remove the application's ability
to customize ForkJoinPool behavior, in particular the use of custom threads.
ForkJoinPool.commonPool()
public void setParallelism(int parallelism)
Runtime.availableProcessors()
.public void setThreadFactory(ForkJoinPool.ForkJoinWorkerThreadFactory threadFactory)
ForkJoinPool.defaultForkJoinWorkerThreadFactory
.public void setUncaughtExceptionHandler(Thread.UncaughtExceptionHandler uncaughtExceptionHandler)
public void setAsyncMode(boolean asyncMode)
true
) may be more appropriate
than the default locally stack-based mode in applications in which worker threads only
process event-style asynchronous tasks. Default is false
.public void setAwaitTerminationSeconds(int awaitTerminationSeconds)
By default, this ForkJoinPool won't wait for the termination of tasks at all. It will continue to fully execute all ongoing tasks as well as all remaining tasks in the queue, in parallel to the rest of the container shutting down. In contrast, if you specify an await-termination period using this property, this executor will wait for the given time (max) for the termination of tasks.
Note that this feature works for the "commonPool"
mode as well. The underlying ForkJoinPool won't actually terminate in that
case but will wait for all tasks to terminate.
public void afterPropertiesSet()
InitializingBean
BeanFactory
after it has set all bean properties
and satisfied BeanFactoryAware
, ApplicationContextAware
etc.
This method allows the bean instance to perform validation of its overall configuration and final initialization when all bean properties have been set.
afterPropertiesSet
in interface InitializingBean
public ForkJoinPool 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<ForkJoinPool>
null
)FactoryBeanNotInitializedException
public Class<?> 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<ForkJoinPool>
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
.
isSingleton
in interface FactoryBean<ForkJoinPool>
FactoryBean.getObject()
,
SmartFactoryBean.isPrototype()
public void destroy()
DisposableBean
BeanFactory
on destruction of a bean.destroy
in interface DisposableBean