Enterprise JavaBeans, 3.0

6.1. The Programming Model Entities are plain Java classes in Java Persistence. You declare and allocate these bean classes just as you would any other plain Java object. You interact with the entity manager service to persist, update, ...

6.2. Basic Relational Mapping A developer can take two directions when implementing entity beans. Some applications start from a Java object model and derive a database schema from this model. Other applications have an exis...

6.3. Primary Keys A primary key is the identity of a given entity bean. Every entity bean must have a primary key, and it must be unique. Primary keys can map to one or more properties and must map to one of the following types: any Java primitive...

6.4. Property Mappings So far, we have only shown how to specify column mappings for simple primitive types. There are still a few bits of metadata that you can use to fine-tune your mappings. In this section, you'll learn more annot...

6.5. Multitable Mappings with @SecondaryTable Sometimes you have to deal with one logical entity that is stored in two different tables. You want one entity bean class to represent your object, but it is mapped into two d...