The posts here that point to examples of Spring + FDS and separate examples of Hibernate + FDS and then say combining the two should be easy seem to be missing the point. This is not as easy an straight forward as it seems it should be.
Spring + Hibernate + FDS is a completely different animal because you are getting Spring to handle the Session Factory configuration and your DAO's as Spring beans but you also want the handling of lazy initialization and proxy serialization as shown in the HibernateAssembler.
The current HibernateAssembler code handles all of the Hibernate setup. I would much rather have Spring do this. What I would like is for my HibernateProxy's for non initialized associations to be serialized rather than traversed resulting LazyInitializationExceptions. The HibernateAssembler seems to tackle this with a very mysterious piece of code:
PropertyProxyRegistry.getRegistry().register(HibernateProxy.class, new HibernatePropertyProxy());
PropertyProxyRegistry and HibernatePropertyProxy are not documented anywhere, and in fact a Google on PropertyProxyRegistry returns 0 results. However, my intuition tells me this piece of code should tell serialization to proxy the HibernateProxy with a flex class called HibernatePropertyProxy which will just serialize an id of an association rather than attempting to serialize the uninitialized associated class.
I cannot get this to work though and as there is no documentation and no discussion on these classes, I have no way of verifying it. If my intuition is correct, this is a very useful mechanism. I only wish it was documented b/c if it did work as expected it would make a Hibernate + Spring + FDS implementation pretty easy.