org.springframework.ejb.support
Class AbstractStatelessSessionBean

java.lang.Object
  org.springframework.ejb.support.AbstractEnterpriseBean
      org.springframework.ejb.support.AbstractSessionBean
          org.springframework.ejb.support.AbstractStatelessSessionBean

All Implemented Interfaces:

Serializable, EnterpriseBean, SessionBean, SmartSessionBean

public abstract class AbstractStatelessSessionBean
extends AbstractSessionBean

Convenient superclass for stateless session beans (SLSBs), minimizing the work involved in implementing an SLSB and preventing common errors. Note that SLSBs are the most useful kind of EJB.

As the ejbActivate() and ejbPassivate() methods cannot be invoked on SLSBs, these methods are implemented to throw an exception and should not be overriden by subclasses. (Unfortunately the EJB specification forbids enforcing this by making EJB lifecycle methods final.)

There should be no need to override the setSessionContext() or ejbCreate() lifecycle methods.

Subclasses are left to implement the onEjbCreate() method to do whatever initialization they wish to do after their BeanFactory has already been loaded, and is available from the getBeanFactory() method.

This class provides the no-argument ejbCreate() method required by the EJB specification, but not the SessionBean interface, eliminating a common cause of EJB deployment failure.

Author:

Rod Johnson

See Also:

Serialized Form

Field Summary

protected Log

logger

Fields inherited from class org.springframework.ejb.support.AbstractEnterpriseBean

BEAN_FACTORY_PATH_ENVIRONMENT_KEY

Constructor Summary

AbstractStatelessSessionBean()

Method Summary

void	ejbActivate()
void	ejbCreate() This implementation loads the BeanFactory.
void	ejbPassivate()
protected abstract void	onEjbCreate() Subclasses must implement this method to do any initialization they would otherwise have done in an ejbCreate() method.

Methods inherited from class org.springframework.ejb.support.AbstractSessionBean

getSessionContext, setSessionContext

Methods inherited from class org.springframework.ejb.support.AbstractEnterpriseBean

ejbRemove, getBeanFactory, loadBeanFactory, onEjbRemove, setBeanFactoryLocator, setBeanFactoryLocatorKey, unloadBeanFactory

Methods inherited from class java.lang.Object

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

Methods inherited from interface javax.ejb.SessionBean

ejbRemove

Field Detail

logger

protected final Log logger

Constructor Detail

AbstractStatelessSessionBean

public AbstractStatelessSessionBean()

Method Detail

ejbCreate

public void ejbCreate()
               throws CreateException

This implementation loads the BeanFactory. A BeansException thrown by loadBeanFactory will simply get propagated, as it is a runtime exception.

Don't override it (although it can't be made final): code your own initialization in onEjbCreate(), which is called when the BeanFactory is available.

Unfortunately we can't load the BeanFactory in setSessionContext(), as resource manager access isn't permitted there - but the BeanFactory may require it.

Throws:

CreateException

onEjbCreate

protected abstract void onEjbCreate()
                             throws CreateException

Subclasses must implement this method to do any initialization they would otherwise have done in an ejbCreate() method. In contrast to ejbCreate, the BeanFactory will have been loaded here.

The same restrictions apply to the work of this method as to an ejbCreate() method.

Throws:

CreateException

ejbActivate

public void ejbActivate()
                 throws EJBException

Throws:

EJBException

See Also:

This method always throws an exception, as it should not be invoked by the EJB container.

ejbPassivate

public void ejbPassivate()
                  throws EJBException

Throws:

EJBException

See Also:

This method always throws an exception, as it should not be invoked by the EJB container.