org.springframework.ejb.support
Class AbstractMessageDrivenBean

java.lang.Object
  org.springframework.ejb.support.AbstractEnterpriseBean
      org.springframework.ejb.support.AbstractMessageDrivenBean

Direct Known Subclasses:

AbstractJmsMessageDrivenBean

public abstract class AbstractMessageDrivenBean
extends AbstractEnterpriseBean

Convenient base class for EJB 2.x MDBs. Doesn't require JMS, as EJB 2.1 MDBs are no longer JMS-specific; see the AbstractJmsMessageDrivenBean subclass.

This class ensures that subclasses have access to the MessageDrivenContext provided by the EJB container, and implement a no-arg ejbCreate() method as required by the EJB specification. This ejbCreate() method loads a BeanFactory, before invoking the onEjbCreate() method, which is supposed to contain subclass-specific initialization.

NB: We cannot use final methods to implement EJB API methods, as this violates the EJB specification. However, there should be no need to override the setMessageDrivenContext or ejbCreate() methods.

Author:

Rod Johnson

Field Summary

protected Log	logger Logger available to subclasses
private MessageDrivenContext	messageDrivenContext

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

BEAN_FACTORY_PATH_ENVIRONMENT_KEY

Constructor Summary

AbstractMessageDrivenBean()

Method Summary

void	ejbCreate() Lifecycle method required by the EJB specification but not the MessageDrivenBean interface.
protected MessageDrivenContext	getMessageDrivenContext() Convenience method for subclasses to use.
protected abstract void	onEjbCreate() Subclasses must implement this method to do any initialization they would otherwise have done in an ejbCreate() method.
void	setMessageDrivenContext(MessageDrivenContext messageDrivenContext) Required lifecycle method.

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

Field Detail

logger

protected final Log logger

Logger available to subclasses

messageDrivenContext

private MessageDrivenContext messageDrivenContext

Constructor Detail

AbstractMessageDrivenBean

public AbstractMessageDrivenBean()

Method Detail

setMessageDrivenContext

public void setMessageDrivenContext(MessageDrivenContext messageDrivenContext)

Required lifecycle method. Sets the MessageDriven context.

Parameters:

messageDrivenContext - MessageDrivenContext

getMessageDrivenContext

protected final MessageDrivenContext getMessageDrivenContext()

Convenience method for subclasses to use.

Returns:

the MessageDrivenContext passed to this EJB by the EJB container

ejbCreate

public void ejbCreate()

Lifecycle method required by the EJB specification but not the MessageDrivenBean interface. This implementation loads the BeanFactory.

Don't override it (although it can't be made final): code 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 and the BeanFactory may require it.

onEjbCreate

protected abstract void onEjbCreate()

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.