In Chapter 5, we discussed the need to create mappings between the database model and the object model. Mappings can be created in two different ways: via inline annotations (as we’ve done through the book so far), or as separate XML files in one of two primary formats.
The XML-based mapping is rarely used outside of situations where mapping an object model to a preexisting schema is required; even then, adept use of the annotations can match the XML ...