Which technologies are you using for your DAO?
If you are using straight Java EE - JPA Entities + Session Bean Facade, then you can certainly follow Frank's suggestion above. OEPE can help you create your JPA Entities and create a Stateless Session Bean which includes the basic CRUD operations (Session Bean from JPA Entities is the wizard name).
If you are using Spring, OEPE has some code generation features to create a Spring Bean from your JPA Entities which includes basic CRUD. We also have some code generation tools to create a JAX-WS service from a spring bean (New > Oracle > WebLogic > Web Service from Spring Bean).
So depending on your technology stack, we should have some features to at least get you started.