Is there a way to config session "transparent write behind" behavior? If I want to only sync up session in memory objects that I called session.saveOrUpdate, not the in memory objects that I modified, how do I do that?

the reason I want to do this is because I want to generate event on every save call. I do not want hibernate to write behind transparently. Is there a way to do this?

We are using hibernate 3.1.3 and Spring framework.

As far as I know, every attached object (meaning that the object obtained through the EntityManager) is going to be checked for changes at session flush time. So what's left for you is to detach the object. There are two ways to do that: use EntityManager.clear() to detach all objects; or get the Hibernate underlying session and evict() a single object. Call saveOrUpdate only after detaching objects. Note that an evited object is not guaranteed to not be saved if it is in a cascade chain.

You can achieve that by implementing an entity listener or an entity lifecycle callback method. Piece of cake if you're using annotations.
Consider thoroughly your objective before choosing an approach (these or others).

It is very easy to do. Hibernate 3 provides an easy-to-use event architecture. You can register a custom Interceptor if you want, or register for a particular event for example.

See http://www.hibernate.org/hib_docs/v3/re ... vents.html