The UML guide is intended to allow architects and Java developers new to JavaGen or Poseidon to be productive as quickly as possible.
The main advantage of using JavaGen is to leverage the high-level abstractions of UML diagrams. To be productive with JavaGen you should think in terms of simple models with an emphasis on creating a solid structure to hang your business logic on.
For example to model an EJB domain tier you just specify the entities, their attributes and the associations, not the implementation details. JavaGen takes care of the EJB bean, home and deployment details. If your modeling EJB homes your not using the tool properly.
JavaGen primarily generates static infrastructure code like pesistance tiers. The Class Diagram is the primary means of specifying structure and is covered extinsivley in the next section. UML Stereotypes are a standard UML extension and are used by JavaGen to trigger specific code generation modules.