posted 19 years ago
Stateful session bean: When client calls create(...), a new EJB object and a new bean instance is created by the container.
Stateless session bean: Bean creation and EJBObject creation are not tied to each other. The bean will not be tied to the EJBObject until the client makes a business method call.
Entity Beans: Bean instance creation and entity creation are not tied to each other. ejbCreate() is called on the bean before even creating an EJB object (primary key is required). And there are differences on who creates the entity in the underlying store between BMP and CMP entity beans.
MDB: Bean pulled out from the pool by container to service a message request from messaging service. (of course no client/home+remote interfaces here!)
If you look at the sequence diagrams for creation of the different bean types in HFEJB, you will notice that the order changes.
Regards<br />Ram<br /> <br />SCJP 1.4, SCBCD 1.3, (SCEA)