Criteria on joining fails

[Ergin Er]

Hi all,

First of all this is my first post on this forum

I'm working on genereating a criteria that will return a list of data from two joined tables.
The tables involved are:
Domain (pk id, fk ppo_id, name)
Workmate (pk id, fk domain_id, fk ppo_id, name, ...)

So I need a statement like this:

 select this.ID as ID0_, this.PPO_ID as PPO_ID0_, this.DOMAIN_ID as DOMAIN_ID0_, this.FIRSTNAME as FIRSTNAME0_
from WORKMATE this inner join Domain that on this.DOMAIN_ID = that.id
where (this.PPO_ID=24) and that.NAME like '%' 

this statement will vary depending on input filters
(domain name, search string)

I'm using criteria to handle this.

 Criteria dom =session.createCriteria(Domain.class);
if (!workmate.getDomainId().equals(new Integer(0))){
       dom.add( Expression.like( "id", workmate.getDomainId().toString()));
} else if (workmate.getDomainId().equals(new Integer(0))) {
dom.add( Expression.like( "id", "'%'"));
} 

if(!search.equalsIgnoreCase("")) {
dom.add( Expression.like("name", search, MatchMode.ANYWHERE));
} else {
dom.add( Expression.like("name", "'%'", MatchMode.ANYWHERE));
}

[B]Criteria wm = dom.createCriteria("workmate");[/B]
if (!search.equalsIgnoreCase("")) {
       wm.add( Expression.like( "firstname", search, MatchMode.ANYWHERE));
       wm.add( Expression.like( "lastname", search, MatchMode.ANYWHERE));
} 
if (workmate.getIsActive() != null) {
       wm.add( Expression.like( "isactive" , workmate.getIsActive(), MatchMode.ANYWHERE));
}
wm.list(); 

It quits when I second create criteria adding workmate to the equasion. I think this might be happening because the pk name and fk name from respective tables are not equal. Is this the case?
If so, how can I add the createria saying it should look at the id as a key to join. Or am I missing something else?
Or should I just use Query to generate the sql?

Any help would be appreciated in this matter.

Update:
This problem was caused by not implementing the tables bi-directionally. I only has a unidirectional refernce saying in workmate it has a fk pointing to domain id. I also needed to make clear to domain table that it has "children" in the workmate table (workmates). With that it now walks through the criteria.
[ September 08, 2005: Message edited by: Ergin Er ]