Uniqueness on basis of the arbitrary properties of my object model

My applicaiton has a very uniqure requirement :) (everyone thinks so)

I have my object model:

[code]
public class Person{
private String firstName = null;
private String lastName = null;
private Address address = null;
}
[/code]

My table is legacy. I want to ignore its PK constraints altogther - just to share with you guys we have a few coloums which make a composite key. I dont want to use all columns to define uniqueness.

Thus I want to make my own arbitraty properties to define uniquness. At least from my applications perspective.

I want that a combination of firstName and lastName to be checked for uniqueness before an insert takes place.

I tried to use the <composite-id> but it does not seem to do this. I really am stuck and really want hibernate to do this for me.

I am using Hibernate 3.1 - just to share with people who love hibernate did you notice all these crazy files in the download of hiberate 3.1. It has plethora of JBoss stuff. I think it is a matter of time we will see this lean mean machine hibernate become a elephant -- like IBM. Thanx for Gavin for a visit to Sun's team but his art for simplicity should remain. Unlike Sun where everything is like the JDO spec which was an obvious flop since its inception. Castor JDO was excellent but those guys just missed the whole thing because of it [b]intrusiveness[/b].

Only tools which are lean and mean and do the job with simplicity are the ones which will survive the this rat race of open source.

hibernate does not do any data validation. you have to do it yourself.