How do you implement callbacks in EJB?

Robert Castaneda

If your client is an EJB, it can pass a reference to itself to the method of the bean that it is calling. The EJB can then call methods directly on that interface.

If your client is a Java client, your client requires some sort of object that will "listen" for call-backs. This could be either a CORBA or RMI object. Again, you could pass references to these objects to the EJB, which could then invoke methods on the references.