Hi, I am looking for advice on how to set up a fairly simple mapping which I'm having trouble with:

I have 2 tables - Agreement and Product - and 2 classes - ClassA and ClassB.
ClassA is directly mapped to the Product table and has a SET of B objects, but each instance af ClassA with EACH instance of ClassB is what constitutes one entity, so I think this is basically a COMPOSITE and a SET that have to be somehow nested together.
The problem is that Class B actually maps some columns to Agreement table and some to Product table.

So my question is this:
How do I nest the ClassB SET into the mappings as a COMPONENT of ClassA, and even more confusing to me, how do I then map ClassB to some columns in Product and some columns in Agreement?

Thanks in advance for any help. It's very much appreciated!