Types of Beans
The
EJB 2.0 specification defines three types of enterprise beans:
- session beans are the actions that must take place, such as making a reservation, charging a credit card, etc. When a client wants to take one of these actions, it calls the session bean. The session bean decides what data to move, but to move this data, it must use an entity bean.
- entity beans, on the other hand, deal with the data. They represent nouns, such as frequent flier account, customer, payment information, etc.
- message driven beans are similar to session beans, except they communicate with messages. We probably will not go into much deatil with message driven beans.
- Take a moment to think of more examples of session beans and enterprise beans.