org.springframework.orm.jdo.support
Class StandardPersistenceManagerProxyBean

java.lang.Object
  org.springframework.orm.jdo.support.StandardPersistenceManagerProxyBean

All Implemented Interfaces:

FactoryBean<javax.jdo.PersistenceManager>

public class StandardPersistenceManagerProxyBean
extends Object
implements FactoryBean<javax.jdo.PersistenceManager>

Proxy that implements the PersistenceManager interface, delegating to a thread-bound PersistenceManager on each invocation - as defined by the JDO 2.1 specification. This class makes such a standard JDO PersistenceManager proxy available for bean references.

The main advantage of this proxy is that it allows DAOs to work with a plain JDO PersistenceManager reference in JDO 2.1 style (see PersistenceManagerFactory.getPersistenceManagerProxy()), exposing the exact behavior that the target JDO provider implements.

Note: This proxy requires JDO 2.1 or higher.

Since:

3.0

Author:

Juergen Hoeller

See Also:

SpringPersistenceManagerProxyBean, PersistenceManagerFactory.getPersistenceManagerProxy()

Constructor Summary

StandardPersistenceManagerProxyBean()

Method Summary

javax.jdo.PersistenceManager	getObject() Return an instance (possibly shared or independent) of the object managed by this factory.
Class<? extends javax.jdo.PersistenceManager>	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	setPersistenceManagerFactory(javax.jdo.PersistenceManagerFactory pmf) Set the target JDO PersistenceManagerFactory that this proxy should delegate to.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

StandardPersistenceManagerProxyBean

public StandardPersistenceManagerProxyBean()

Method Detail

setPersistenceManagerFactory

public void setPersistenceManagerFactory(javax.jdo.PersistenceManagerFactory pmf)

Set the target JDO PersistenceManagerFactory that this proxy should delegate to. This should be the raw PersistenceManagerFactory, as accessed by JdoTransactionManager.

See Also:

JdoTransactionManager

getObject

public javax.jdo.PersistenceManager 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<javax.jdo.PersistenceManager>

Returns:

an instance of the bean (can be null)

See Also:

FactoryBeanNotInitializedException

getObjectType

public Class<? extends javax.jdo.PersistenceManager> 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<javax.jdo.PersistenceManager>

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 object managed by this factory a singleton? That is, will 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.

Specified by:

isSingleton in interface FactoryBean<javax.jdo.PersistenceManager>

Returns:

whether the exposed object is a singleton

See Also:

FactoryBean.getObject(), SmartFactoryBean.isPrototype()