We want to split our product into several components that the client can buy independently of each other. Nevertheless associations between the involved entities should be bidirectional. Let's say we have a Client Entity in our base component. We want to have bidirectional associations to this Entity from independent entities, like: CarShop.getClient(), Museum.getClient(), where CarShop and Museum don't know of each other's existence.

What's the best practice to achieve such modularity?
One approach I can see is to have all possible associations in the pojos and "activate" the possible ones upon startup in the mapping xml.

Another approach may be to modify the way hibernate discovers the mappings and add our own extra associations programmatically.

I've found some descriptions on how to add simple fields using a Map, but I haven't found a resource for adding associations and I am not sure what I have to change in AnnotationConfiguration or Configuration.

Ok, after reading this blog entry:
http://out-println.blogspot.com/2010/01/hibernate-disabling-all-lazy.html

I've decided to do something along these lines:


I'll report back on how it went.

Ok, I've managed to figure out what attributes to set how, but the problem is now to write a custom PropertyAccessor that does not need a field in the pojo. I've hacked something but I'm still at a loss how to make hibernate use my custom propertyaccessor.

Managed to do that too, now I'm struggling to do the same thing for OneToMany assocations. The Problem is that this isn't a simpleValue anymore and I'll have to figure out a way to get my role->collection mapping in the MappingsImpl.