Hi,

Is it possible to create an expression on attributes of an associated object by using just Expression and not createCriteria() for the association ?

I'd like to keep the layer in my application that constructs the expressions free from the Criteria stuffm and just pass in a collection of Expressions for the query. If I use createCriteria, I have to handle Hibernate exceptions, and have access to the Hibernate session, which I've abstracted out at the lower layer too.

Initially I thought that dot notation would work for associations, for example I could do the following (using a User object with an associated Address):



where queryWithCriteria() constructs the actual Criteria using the list, and calls .list();

It seems that the dot notation works for components, but not for associtions, so I'd have to have access to the Criteria at the higher level, which kind of breaks my nice abstraction :-(

Any ideas ?

Cheers,
Darren.

Well, you can parse your expression at a lower level and manually break it up in your code where you build your criteria query.

Yeah, I was thinking along these lines at first myself.

If I parsed the dot notation and created my own Criteria I'd break the use of the dot notation for components. I suppose I could use another convention.

I'm now thinking along the lines of creating a custom Criterion (something like AssociationEqExpression which would have to override the getColumns() in the AbstractCriterion class and implement its own toSqlString(..) (and not extent SimpleExpression.

Does this sound a reasonable approach to anyone, or am I heading too far off track ??

Cheers,
Darren.

How would you add in the necessary join? Well, I guess its possible....


If you manage to get something like this working, please share, it would be really great if we could get it in the HIbernate core!