I have created a few of these, but I have not seen any documentation on how it is referenced internally. Is it safe to use member variables in these classes? Would/should there be a case that any of the functions ( ie nullSafeSet, nullSafeGet ) are synchronized?

Thanks in advance for any information, the help is much appreciated.

Currently, yes it is safe. Hibernate will create a new instance every time the UserType is referenced in the mapping document.

Unfortunately, as you said, the API doesn't say anything about this behavior. Not written in the API, so be careful...



I don't think so. The Hibernate Session cannot be shared by multiple threads - and afaik Hibernate is not multithreaded. Therefore can't see any reasons why you should protect your methods with the synchronize keyword.

Hibernate is thread safe in SessionFactory