Does anyone have full source examples of the data access / business objects within the Spring AOP with Hibernate Wiki tutorial?

http://www.springframework.org/docs/...Hibernate.html

I'm a bit confused as to the separate of code within MyBusinessObjectImpl, MyBusinessObjectTarget, and MyBusinessObject.

I think it would be helpful for me if I had actual source with which to compare the configuration file references.

Do all my business logic classes extend a parent MyBusinessObjectImpl? Or do all my business logic classes implement MyBusinessObject?

(As you see, one of confusing points is that the naming conventions are a bit too generic.)

Lukas