Will hibernate ever support bidirectional any associations? I mean where the reference is made by a pair of kind-id instead of a normal fk, so that the target could be of different kind~class~entity~table (of course, fk constraints should not be generated here). I've tried a number of workarounds but they are far from ideal (custom queries, @where clauses, unidirectional any associations). I think this is a nice to have since associations to interfaces are pretty common and sometimes it's very difficult to map them to any of the hierarchy mappings that hibernate provides, because any class can implement an interface, not just a class that inherits from some common root. And although against database purisms it's a customary solution when the entity association needs to be flexible enough.

Cheers,
Carlos

Mh, just before anyone answers this, here is an obvious solution that doesn't work that good:

For a one-to-many bidirectional association:

1) at the source side use an any association

2) at each class at the target side (discriminated by kind) use a one-to-many association with a where clause to get the sources of the right kind

Well the problem is that each of the one-to-many associations generate a different fk constraint for the source side, and these constraints can't be fullfilled all at the same time because they don't take into account the kind field but just require that the source id field, when not null, references each of the target kinds simulateously.

Cheers,
Carlos