Store childdata of two classes in one table

nola · **Joined:** Wed Apr 25, 2007 8:23 am **Posts:** 8

Hi,

how to map this:

Code:

class A {
Set<class C>
}

Code:

class B {
Set<class C>
}

Every class should be mapped to one table.
Class A and B can have same values for their ids in the tables.

Sets of C are disjoint for A and B.

I haven't found any solution, yet.

Thanks !

(Using Hibernate3)

saugata · **Joined:** Thu May 17, 2007 5:29 am **Posts:** 13

Option 1> Keep two id columns in C : id_A, id_B, for any row one would be null, the other pointing to the parent.
Option 2> Keep Set<C> in a separate class D, and add methods in A/B to convert to/from D to Set<C>, so A/B contain foreign keys to D, while D contains Set<C>. (Don't map A.set, rather map A.d)

The first one will not involve any code change.

nola · **Joined:** Wed Apr 25, 2007 8:23 am **Posts:** 8

Thanks saugata,

but where can I place the mapping for C ?
Is it twice in the mapping for A and B,
with the little difference you described ?

nola