Appendix E. EJB 3.0 Entity Inheritance Hierarchies


JPA provides declarative support for three main implementation strategies that dictate how the entities in a hierarchy map to underlying tables.

To illustrate how these three strategies are manifested in code, we will use the sample entity hierarchy that demonstrates inheritance:

Sample entity hierarchy

The Person entity serves as the root class in an entity hierarchy, and is extended by the Employee entity.

NOTE: The source code for this tutorial can be downloaded as a zip archive.

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