Hello there! We have a very concurrent application. Our entity have a value that is incremented by one every time it is updated. We ran in a concurrency problems here.

The code is as follow:

Entity entity = dao.get(pk);//ensure that we have the last persisted one
entity.setValue(entity.getValue()+1);
dao.update(entity);

I guess you guys figured out what's going on... we are reading stale data, a user reads value 123 for example, and just before he updates with value 124, another user already did, now, something that should be 125 is 124.

We could add synchronize to our java method, but this may lead to bottlenecks. Also we could use triggers (but we don't want to have this kind of rules in the DB).

Does hibernate provide a way of doing this? I was thinking about Interceptors, are they thread safe?

Best Regards

http://www.hibernate.org/hib_docs/v3/re ... optimistic

The column type you are describing maps directly to a 'version'. There are quite a bit of resources on the web with how to handle optimistic concurrency control. Start with the link above.