FWIW, if only the XyLoadAccess types are generified, I find it's much less useful than it could be. Isn't get()/load() what is used in 95% of the cases? I find the proposal of generifying get()/load() (i.e. altering the existing methods, not adding new variants) attractive; Requiring the proxy interface to be passed in such cases (as suggested by Emmanuel Bernard) seems acceptable to me.