I need to map the following hierarchy, but am not successful in creating
the appropriate mapping document:


What I would like to end up with are 4 tables: one for DrawingTool and
one for each of the hierarchy bases (Raster,Vector,Type) etc.

Is it possible to do? I read the documentation and I am confused. It
seems to me that it is possible to create a mapping where the concrete
classes are mapped to separate tables and are joined, but I cannot
find a mapping that would create the set of tables I would like to have.

The reason for this mapping is that whilst for the most part (and the
example above is contrived) I will need to access instances using
the hierarchy bases (Raster, Vector, etc), I also need to be able to
access/store collections of these instances polymorphically.

Hibernate version: 3.0b4

Any help would be appreciated.

Cheers,

Bonny

I've had another look through the docs and whilst I understand
that one could have a polymorphic association with superclasses
using the <any> mechanism, I would still like to pursue the concept
mapping as I've drawn above.

Could anyone please say whether it is possible to do and also what
performance implications there are when choosing either method?

Currently this is not possible, leaf classes would need to have their own tables. I'd like to be able to handle this case though.

Gavin,

Thanks for the reply. Does this mean that I cannot (even with the <any>
construct) create a collection representing a one-to-many relationship
like (this is the impression
I get from the Hibernate reference document)