Using JPA to partially initialize entities
Posted on 2011-02-17
I have created an application with a relatively complex model. Everything was working fine and the beta-tests were running smoothly. The problem I am having is that I am using BlazeDS to send results to a Flex client. This causes all relations to be loaded (even if they are marked for lazy loading) and sent to the client. This is rather undesirable as a simple listEntityA doesn't only return a list of EntityA but also all of their references and the references of their references ... a lot of stuff.
I know in JPA I can do these really cool "SELECT NEW packagename.Classname(params...) FROM ..." to create unmanaged instances that are partially initialized (projections). The problem is, that I really would like the main entity to be fully initialized, but I would love some related objects to be only initialized with let's say "id" and "name" (all other properties left empty) ... this would be a projection of the relation.
How could I do this?