What is an Enterprise Java Bean really?

Question

On the Tomcat FAQ it says: \"Tomcat is not an EJB server. Tomcat is not a full J2EE server.\"

But if I:

• use Spring to supply an application context
<

Answer 1

EJBs are JavaEE components that conform to the javax.ejb API.

JavaEE is a collection of APIs, you don't need to use all of them.

Tomcat is a "partial" JavaEE server, in that it only implements some of the JavaEE APIs, such as Servlets and JNDI. It doesn't implement e.g. EJB and JMS, so it's not a full JavaEE implementation.

If you added some additional bits and pieces (e.g. OpenEJB, HornetQ), you'd add the missing parts, and you'd end up with a full JavaEE server. But out of the box, Tomcat isn't that, and doesn't try to be.