org.springframework.ejb.access

Class LocalStatelessSessionProxyFactoryBean

  • All Implemented Interfaces:
    Advice, Interceptor, MethodInterceptor, Aware, BeanClassLoaderAware, FactoryBean<java.lang.Object>, InitializingBean


    public class LocalStatelessSessionProxyFactoryBean
    extends LocalSlsbInvokerInterceptor
    implements FactoryBean<java.lang.Object>, BeanClassLoaderAware
    Convenient FactoryBean for local Stateless Session Bean (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 LocalSlsbInvokerInterceptor 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).

    Since:
    09.05.2003
    Author:
    Rod Johnson, Colin Sampaleanu
    See Also:
    AbstractSlsbInvokerInterceptor.setLookupHomeOnStartup(boolean), AbstractSlsbInvokerInterceptor.setCacheHome(boolean)
    • Constructor Detail

      • LocalStatelessSessionProxyFactoryBean

        public LocalStatelessSessionProxyFactoryBean()
    • Method Detail

      • setBusinessInterface

        public void setBusinessInterface(@Nullable
                                         java.lang.Class<?> businessInterface)
        Set the business interface of the EJB we're proxying. This will normally be a super-interface of the EJB local component interface. Using a business methods interface is a best practice when implementing EJBs.
        Parameters:
        businessInterface - set the business interface of the EJB
      • getBusinessInterface

        @Nullable
        public java.lang.Class<?> getBusinessInterface()
        Return the business interface of the EJB we're proxying.
      • getObject

        @Nullable
        public java.lang.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<java.lang.Object>
        Returns:
        an instance of the bean (can be null)
        See Also:
        FactoryBeanNotInitializedException
      • getObjectType

        public java.lang.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<java.lang.Object>
        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<T>)
      • 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.

        The default implementation returns true, since a FactoryBean typically manages a singleton instance.

        Specified by:
        isSingleton in interface FactoryBean<java.lang.Object>
        Returns:
        whether the exposed object is a singleton
        See Also:
        FactoryBean.getObject(), SmartFactoryBean.isPrototype()