org.springframework.ejb.access
Class SimpleRemoteStatelessSessionProxyFactoryBean

java.lang.Object
  org.springframework.jndi.JndiAccessor
      org.springframework.jndi.JndiLocatorSupport
          org.springframework.jndi.JndiObjectLocator
              org.springframework.ejb.access.AbstractSlsbInvokerInterceptor
                  org.springframework.ejb.access.AbstractRemoteSlsbInvokerInterceptor
                      org.springframework.ejb.access.SimpleRemoteSlsbInvokerInterceptor
                          org.springframework.ejb.access.SimpleRemoteStatelessSessionProxyFactoryBean

All Implemented Interfaces:

Advice, Interceptor, MethodInterceptor, BeanClassLoaderAware, DisposableBean, FactoryBean, InitializingBean

public class SimpleRemoteStatelessSessionProxyFactoryBean
extends SimpleRemoteSlsbInvokerInterceptor
implements FactoryBean, BeanClassLoaderAware

Convenient factory for remote SLSB proxies. Designed for EJB 2.x, but works for EJB 3 Session Beans as well.

See JndiObjectLocator for info on how to specify the JNDI location of the target EJB.

If you want control over interceptor chaining, use an AOP ProxyFactoryBean with SimpleRemoteSlsbInvokerInterceptor rather than rely on this class.

In a bean container, this class is normally best used as a singleton. However, if that bean container pre-instantiates singletons (as do the XML ApplicationContext variants) you may have a problem if the bean container is loaded before the EJB container loads the target EJB. That is because by default the JNDI lookup will be performed in the init method of this class and cached, but the EJB will not have been bound at the target location yet. The best solution is to set the lookupHomeOnStartup property to false, in which case the home will be fetched on first access to the EJB. (This flag is only true by default for backwards compatibility reasons).

This proxy factory is typically used with an RMI business interface, which serves as super-interface of the EJB component interface. Alternatively, this factory can also proxy a remote SLSB with a matching non-RMI business interface, i.e. an interface that mirrors the EJB business methods but does not declare RemoteExceptions. In the latter case, RemoteExceptions thrown by the EJB stub will automatically get converted to Spring's unchecked RemoteAccessException.

Since:

09.05.2003

Author:

Rod Johnson, Colin Sampaleanu, Juergen Hoeller

See Also:

RemoteAccessException, AbstractSlsbInvokerInterceptor.setLookupHomeOnStartup(boolean), AbstractSlsbInvokerInterceptor.setCacheHome(boolean), AbstractRemoteSlsbInvokerInterceptor.setRefreshHomeOnConnectFailure(boolean)

Field Summary

Fields inherited from class org.springframework.jndi.JndiLocatorSupport

CONTAINER_PREFIX

Fields inherited from class org.springframework.jndi.JndiAccessor

logger

Constructor Summary

SimpleRemoteStatelessSessionProxyFactoryBean()

Method Summary

void	afterPropertiesSet() Fetches EJB home on startup, if necessary.
Class	getBusinessInterface() Return the business interface of the EJB we're proxying.
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 object managed by this factory a singleton?
void	setBeanClassLoader(ClassLoader classLoader) Callback that supplies the bean class loader to a bean instance.
void	setBusinessInterface(Class businessInterface) Set the business interface of the EJB we're proxying.

Methods inherited from class org.springframework.ejb.access.SimpleRemoteSlsbInvokerInterceptor

destroy, doInvoke, getSessionBeanInstance, refreshHome, releaseSessionBeanInstance, setCacheSessionBean

Methods inherited from class org.springframework.ejb.access.AbstractRemoteSlsbInvokerInterceptor

getCreateMethod, invokeInContext, isConnectFailure, isHomeRefreshable, lookup, newSessionBeanInstance, refreshAndRetry, removeSessionBeanInstance, setHomeInterface, setRefreshHomeOnConnectFailure

Methods inherited from class org.springframework.ejb.access.AbstractSlsbInvokerInterceptor

create, getHome, invoke, setCacheHome, setExposeAccessContext, setLookupHomeOnStartup

Methods inherited from class org.springframework.jndi.JndiObjectLocator

getExpectedType, getJndiName, setExpectedType, setJndiName

Methods inherited from class org.springframework.jndi.JndiLocatorSupport

convertJndiName, isResourceRef, lookup, lookup, setResourceRef

Methods inherited from class org.springframework.jndi.JndiAccessor

getJndiEnvironment, getJndiTemplate, setJndiEnvironment, setJndiTemplate

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleRemoteStatelessSessionProxyFactoryBean

public SimpleRemoteStatelessSessionProxyFactoryBean()

Method Detail

setBusinessInterface

public void setBusinessInterface(Class businessInterface)

Set the business interface of the EJB we're proxying. This will normally be a super-interface of the EJB remote component interface. Using a business methods interface is a best practice when implementing EJBs.

You can also specify a matching non-RMI business interface, i.e. an interface that mirrors the EJB business methods but does not declare RemoteExceptions. In this case, RemoteExceptions thrown by the EJB stub will automatically get converted to Spring's generic RemoteAccessException.

Parameters:

businessInterface - the business interface of the EJB

getBusinessInterface

public Class getBusinessInterface()

Return the business interface of the EJB we're proxying.

setBeanClassLoader

public void setBeanClassLoader(ClassLoader classLoader)

Description copied from interface: BeanClassLoaderAware

Callback that supplies the bean class loader to a bean instance.

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

Specified by:

setBeanClassLoader in interface BeanClassLoaderAware

Parameters:

classLoader - the owning class loader; may be null in which case a default ClassLoader must be used, for example the ClassLoader obtained via ClassUtils.getDefaultClassLoader()

afterPropertiesSet

public void afterPropertiesSet()
                        throws NamingException

Description copied from class: AbstractSlsbInvokerInterceptor

Fetches EJB home on startup, if necessary.

Specified by:

afterPropertiesSet in interface InitializingBean

Overrides:

afterPropertiesSet in class AbstractSlsbInvokerInterceptor

Throws:

NamingException

See Also:

AbstractSlsbInvokerInterceptor.setLookupHomeOnStartup(boolean), AbstractSlsbInvokerInterceptor.refreshHome()

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 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

Returns:

whether the exposed object is a singleton

See Also:

FactoryBean.getObject(), SmartFactoryBean.isPrototype()