Let me explain the problem I have:



Here is the hibernate mapping I try to do:

class Z do not need a real table, constructor is protected, so no self instance of Z can exist. Those class simply provide common features to subclass.

In fact, I need to have only two database tables :



That all, But I cannot find how to do those map in hibernate.
It seems that is not possible to do the trick like this.

With table-per-hierarchy (<subclass>) strategie mapping we have one big table with discriminator. But this way introduce problem for not null field constraints on subclass.

With table-per-subclass (<joined-subclass>) strategie mapping we will have three databses tables with one-to-one relation between A,Z and B,Z.
(that not what I want for performance reasons)

With table-per-concrete-class (<any>) strategie mapping, it seems that we have to include all Z persistant fields inside A and B. So we must map the 'active' field in all subclass. (I want to avoid to repeat the 'active' field in each subclass)

Is there a way to do the trick without explicitly map the 'acitve' field inside each subclass ? The goal is to provide the 'active' persistant field inside Z class and never have to make map each time we create a new subclass.

Thanks in advance for all your comments.

1. use XML entity to avoid redundancy
2. use xdoclet to generate your mapping files. It'll do the duplication for you