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, Aware, BeanClassLoaderAware, DisposableBean, FactoryBean<Object>, InitializingBean

    public class SimpleRemoteStatelessSessionProxyFactoryBean
    extends SimpleRemoteSlsbInvokerInterceptor
    implements FactoryBean<Object>, BeanClassLoaderAware

Convenient `FactoryBean` 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

Constructors
Constructor and Description
`SimpleRemoteStatelessSessionProxyFactoryBean()`

### Method Summary

Methods
`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? That is, will `FactoryBean.getObject()` always return the same object (a reference that can be cached)?
`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<Object>`
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<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`.

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