Let's say that I have 3 interfaces:
Colour
- getColour/setColour
Position
- getX/setX
- getY/setY
Size
- getSize/setSize

I have different classes that implement 1, 2, or all 3 of the interfaces.

How do I get Hibernate to represent this structure? I would like to be able to do something like:



I would prefer to use <joined-subclass> because the interfaces used in my project have many more "attributes" than the interfaces in this example.

Please refer to the new page on "Inheritance Mappings" in the Hibernate 2.1 final download.

Thanks for the pointer. That page definitely helps clarify a few things.

It seems like I can't set up the tables exactly as I'd like to, so I'm going to propose a future enhancement to the per-subclass strategy: table per subclass and interface. Each interface gets its own table which is referenced by the tables of classes or subclasses that implement it. In my example, it would result in the following tables and columns:

Colour
- key
- colour
Position
- key
- x_coordinate
- y_coordinate
Size
- key
- size
A
- id
- colour_key
- position_key
- size_key

As long as the interfaces don't define getId/setId, I think that it should work.

What do you think?