Is there a direct mechanism in Hibernate that can be used for mapping a collection of polymorphic objects? My limited knowledge of the platform is that (a) Hibernate is always surprising me with what it implements up front, but (b) This mapping is not "relational" in the classical sense of the word, so an Object Relational Mapping is only a partial answer.

For example:

[/code]

Whats your actual problem?

At this time, I am designing the system at a high level. I have used Hibernate successfully in projects where there is a traditional relational model, and I have wroeked out how Hibernate can make coding a polymorphic collection loader much easier.

But, if it is possible, I would like to stick strictly to configurations for defining the collection relationship.

As it is, with my current understanding of Hibernate, I would need an intermediate stub piece to hold lookup information for every item in the collection. The stub would say what instance ID (aka primary key), and what class (aka table), and the loader class would use Hibernate functionality to look up the actual class from the intermediate stubbed data.

I would prefer to use a configuration only and avoid building the loader class, the intermediate lookup stubs and stub table.

At this point, it is still strictly a design problem - nothing has been laid in code or DDL.

Thanks!

I don't really understand your conclusions, but what you need is a common interface you can use as the target for the association, e.g. a common superclass.

If I understand you, then if all of my classes descended from, say, LineItem, and the reference was defined to LineItem, then Hibernate will correctly populate the collection of all pertinent classes (aka from all tables).

So,


then if the other classes all extend LineItem, and the Hibernate mapping is to LineItem, the items in Assembly will be correctly populated and managed by the Hibernate environment.

This is simpler than I had hoped for, if it is true.

Thanks!