Head First EJB

Chapter 4. Session Bean Lifecycle: Being a Session Bean

Session beans are created and removed. If you’re lucky, you’re a stateless bean. Because the life of a stateful bean is tied to the whims of a heartless client. Stateful beans are created at the client’s insistence, and exist only to serve that one client. As a stateful bean, the best you can hope for is that the client crashes or forgets to call remove(); it might take the Container a while to figure out you’ve become useless. But ahhhh, the life of a stateless bean is fabulous! Pools, those little umbrella drinks, and no boredom since you get to meet so many different clients. Of course, even a stateless bean dies with an unchecked exception...

Objectives

Session Beans

Official:		What it really means:
3.1	Identify correct and incorrect statements or examples about session beans, including conversational state, the SessionBean interface, and create methods.	This objective can hit you on anything related to session beans, so you pretty much have to know it all, including the details of both stateless and stateful bean lifecycles, the container callback methods of SessionBean, what you must write in a bean class, and what a bean can get from its EJBContext. Anything covered by the other session bean objectives is fair game.
3.2	Identify the use of, and the behavior of, the ejbPassivate method in a session bean, including the responsibilities ...