Head First EJB

Persistent CMP fields in the DD

Note

The naming convention is REQUIRED!

You must have a pair of abstract getters and setters that have the first character after the “get” and “set” capitalized, but in the CMP field definition in the DD, you start with a lowercase letter, leaving off the “get” and “set”. In other words, you define the CMP field in the DD as if it were a real instance variable, following the old pre-EJB JavaBeans naming convention.

There are no Dumb Questions

Q:	Q: How does the Container know the type of the persistent field? I see a definition for the primary key type (<prim-key-class>, but I don’t see anything for the other CMP fields.
A:	A: The Container figures it out based on the return type and argument of the abstract getters and setters in the bean class. And they had better match! If you have a getLimitNum() that returns an int, you better have a setLimitNum(int i) that takes an int.