Is it possible to derive my EJB class from a standard Java class?

Damien Bootsma

Yes it is possible. Although, naturally you must make sure that the methods of the EntityBean or SessionBean interfaces (depending on which type of EJB you are writing) are implemented either in the Bean class or its' superclasses.
When descending from an existing class, you should be aware of the EJB programming restrictions outlined in section 18.1.2 of the EJB 1.1 specification. For example, You must be careful not to extend from any of the java.io.* classes or java.lang.Thread.