I have a question here that I have no idea how to tackle. How do I write the hbm.xml file to implement the following relationship in hibernate?

I have 2 tables A and B.

The schema are as follows:
A {
id PK
}

B {
id_1 PK, FK
id_2 PK, FK
}

The relationship is that, B.id_1 and B.id_2 combine to form a composite id and each of them is a foreign key in table A (many-to-one).

Thanks in advance!

If I get you right, you mean that every B has 2 As associated and every A has any numbers of Bs assoicated by id_1 and any number by id_2. If yes, this should be doable:

Use two key-many-to-one mappings for two A propertys in your mapping for class B, and use two set mappings relating to B in your mapping for class A

No need to have the bi-directional mapping. Only key-many-to-one inside composite-id in B.

Thanks for the reply. Yeah gloeglm you've got it.
I'll try to do "key-many-to-one" thing.
I'll post the result when it is done.