How to reuse a Criteria object with hibernate?

Question

Criteria.setProjection(null);
Criteria.setResultTransformer(Criteria.ROOT_ENTITY);

Will effectively "reset" the criteria between the rowCount projection and execution of the criteria itself.

I would make sure your Order hasn't been added before doing the rowCount, it'll slow things down. My implementation of PaginatedList ALWAYS runs a count query before looking for results, so ordering isn't an issue.

well, DetachedCriteria are Serializable, so you have built-in (if inelegant) deep clone support. You could serialize the initial criteria to a byte[] once on construction, then deserialize it each time you want to use it.

http://weblogs.asp.net/stefansedich/archive/2008/10/03/paging-with-nhibernate-using-a-custom-extension-method-to-make-it-easier.aspx

In that post I spotted a CriteriaTransformer.clone method.

That should copy the criteria object.

You can also set the projection on your getlist method.

Woops I didn't notice you were referring to java hibernate. Anyway, this http://forum.hibernate.org/viewtopic.php?t=939039

forum post should be able to answer your question.

Ugly as it may be I ended up using the serialization trick. I just serialize the DetachedCriteria object to a byte array on construction of the PaginatedList object and de-serialize it when needed. Ouch.