public class ScopedProxyFactoryBean extends ProxyConfig implements FactoryBean<java.lang.Object>, BeanFactoryAware
Proxies created using this factory bean are thread-safe singletons and may be injected into shared objects, with transparent scoping behavior.
Proxies returned by this class implement the ScopedObject
interface.
This presently allows for removing the 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 by default. This can be customized through switching the "proxyTargetClass" property to "false".
ProxyConfig.setProxyTargetClass(boolean)
,
Serialized FormModifier and Type | Field and Description |
---|---|
private java.lang.Object |
proxy
The cached singleton proxy
|
private SimpleBeanTargetSource |
scopedTargetSource
The TargetSource that manages scoping
|
private java.lang.String |
targetBeanName
The name of the target bean
|
Constructor and Description |
---|
ScopedProxyFactoryBean()
Create a new ScopedProxyFactoryBean instance.
|
Modifier and Type | Method and Description |
---|---|
java.lang.Object |
getObject()
Return an instance (possibly shared or independent) of the object
managed by this factory.
|
java.lang.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 |
setBeanFactory(BeanFactory beanFactory)
Callback that supplies the owning factory to a bean instance.
|
void |
setTargetBeanName(java.lang.String targetBeanName)
Set the name of the bean that is to be scoped.
|
copyFrom, isExposeProxy, isFrozen, isOpaque, isOptimize, isProxyTargetClass, setExposeProxy, setFrozen, setOpaque, setOptimize, setProxyTargetClass, toString
private final SimpleBeanTargetSource scopedTargetSource
private java.lang.String targetBeanName
private java.lang.Object proxy
public ScopedProxyFactoryBean()
public void setTargetBeanName(java.lang.String targetBeanName)
public void setBeanFactory(BeanFactory beanFactory)
BeanFactoryAware
Invoked after the population of normal bean properties
but before an initialization callback such as
InitializingBean.afterPropertiesSet()
or a custom init-method.
setBeanFactory
in interface BeanFactoryAware
beanFactory
- owning BeanFactory (never null
).
The bean can immediately call methods on the factory.BeanInitializationException
public java.lang.Object 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.lang.Object>
null
)FactoryBeanNotInitializedException
public java.lang.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<java.lang.Object>
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<java.lang.Object>
FactoryBean.getObject()
,
SmartFactoryBean.isPrototype()