Persisting complex Embeddable/Embedded objects in Spring/Hibernate
Hibernate and Spring and the Java Persistence packages make for a powerful combination. You can define a complex tree of objects, and the system automagically creates the database schema, and automagically saves and retrieves that object tree from the database. It means you can innocently code away, until one day you try to include an Embedded object but it silently fails to be saved to the database, Hibernate silently fails to create database columns for that object, and when retrieving the object for which the Embedded object is a field, the object is null. No error messages are printed in the log. Instead you're left wondering, why didn't Hibernate persist this object? What's presented here is a solution using EntityListener methods to convert values in and out of shadow values stored in the Entity.