Defining an enterprise bean as a subclass of another enterprise bean is not part of the Enterprise JavaBeans specification. However, in real-life applications, we need this essential feature of object-oriented programming. Direct inheritance is specific to WebSphere Application Server and Studio Application Developer.
Application Developer provides different mapping approaches for an inheritance hierarchy: a single table approach, and a root/leaf approach with foreign key related tables.
In addition, entity beans can inherit from regular Java classes.
The support for EJB inheritance in the IBM tools is not new, and has been around since VisualAge for Java Version 3. EJB 2.0 still does not provide formal support for EJB inheritance, ...