The Spring Framework

org.springframework.aop.scope
Class ScopedProxyFactoryBean

java.lang.Object
  extended by org.springframework.aop.framework.ProxyConfig
      extended by org.springframework.aop.scope.ScopedProxyFactoryBean
All Implemented Interfaces:
Serializable, BeanFactoryAware, FactoryBean

public class ScopedProxyFactoryBean
extends ProxyConfig
implements FactoryBean, BeanFactoryAware

Convenient proxy factory bean for scoped objects.

Proxies created using this factory bean are thread-safe singletons, and may be injected, with transparent scoping behavior.

Proxies returned by this class implement the ScopedObject interface. This presently allows removing corresponding object from the scope, seamlessly creating a new instance in the scope on next access.

Please note that the proxies created by this factory are class-based proxies.

Since:
2.0
Author:
Rod Johnson, Juergen Hoeller
See Also:
Serialized Form

Field Summary
 
Fields inherited from class org.springframework.aop.framework.ProxyConfig
exposeProxy, logger
 
Constructor Summary
ScopedProxyFactoryBean()
          Creates a new instance of the ScopedProxyFactoryBean class.
 
Method Summary
 Object 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 bean managed by this factory a singleton or a prototype?
 void setBeanFactory(BeanFactory beanFactory)
          Callback that supplies the owning factory to a bean instance.
 void setTargetBeanName(String targetBeanName)
          Sets the name of the bean that is to be scoped.
 
Methods inherited from class org.springframework.aop.framework.ProxyConfig
copyFrom, getAopProxyFactory, isExposeProxy, isFrozen, isOpaque, isOptimize, isProxyTargetClass, setAopProxyFactory, setExposeProxy, setFrozen, setOpaque, setOptimize, setProxyTargetClass, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

ScopedProxyFactoryBean

public ScopedProxyFactoryBean()
Creates a new instance of the ScopedProxyFactoryBean class.

Method Detail

setTargetBeanName

public void setTargetBeanName(String targetBeanName)
Sets the name of the bean that is to be scoped.

Parameters:
targetBeanName - the name of the bean that is to be scoped.

setBeanFactory

public void setBeanFactory(BeanFactory beanFactory)
Description copied from interface: BeanFactoryAware
Callback that supplies the owning factory to a bean instance.

Invoked after the population of normal bean properties but before an initialization callback such as InitializingBean.afterPropertiesSet() or a custom init-method.

Specified by:
setBeanFactory in interface BeanFactoryAware
Parameters:
beanFactory - owning BeanFactory (may not be null). The bean can immediately call methods on the factory.
See Also:
BeanInitializationException

getObject

public Object getObject()
Description copied from interface: FactoryBean
Return an instance (possibly shared or independent) of the object managed by this factory.

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.

Specified by:
getObject in interface FactoryBean
Returns:
an instance of the bean (can be null)
See Also:
FactoryBeanNotInitializedException

getObjectType

public Class getObjectType()
Description copied from interface: FactoryBean
Return the type of object that this FactoryBean creates, or 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.

Specified by:
getObjectType in interface FactoryBean
Returns:
the type of object that this FactoryBean creates, or null if not known at the time of the call
See Also:
ListableBeanFactory.getBeansOfType(java.lang.Class)

isSingleton

public boolean isSingleton()
Description copied from interface: FactoryBean
Is the bean managed by this factory a singleton or a prototype? That is, will 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.

Specified by:
isSingleton in interface FactoryBean
Returns:
if this bean is a singleton
See Also:
FactoryBean.getObject()

The Spring Framework

Copyright © 2002-2006 The Spring Framework.