-My mappings specify identity key generation.

-I rely on load() to return proxies, so I can establish associations without doing an actual query.

-My classes are interface/implementation pairs, mapped using implicit polymorphism. I don't specify the interface in the mapping file, but I do run queries and loads against the interface, expecting hibernate to return instances of the implementation.

-You can't load(Interface.class) when using implicit polymorphism.

-union-subclass, which would make load(Interface.class) work, is not compatible with identity key generation.

-oh snap

he;lp[

I kind of sidestepped this by using the Restrictions.idEq() idiom as outlined in the reference docs, and then caching that query. Kind of lame, I'm still looking for a better solution.

Some more things I've tried:

I reasoned that since I only have one unioned subclass, representing the only actual table in the database for that hierarchy, it is not an error to use identity key generation. I copied the code from IdentityGenerator.java into my own class in order to avoid Hibernate's instanceof check and used that as my generator. Unfortunately, some of my <class> mappings have <joined-subclass> mappings, which you can't nest inside a <union-subclass>. You can nest a <subclass><join> in a <union-subclass>, but you can't nest a <set> in turn within a <subclass><join> like you can in a <joined-subclass>.

As a result I'm kind of stuck. How is this actually done? I cannot be the only person encountering this problem.

Look what you've reduced me to. Are you really going to let me get away with this crime against nature? Where's your sense of decency man!