hi,

I want to implement a lastModified / modifiedBy property to all my persisten objects. all my objects subclass "PersistentObject" which already contains those properties. but now i want to implement a mechanism in this superclass that allows me to set those properties (maybe using the callbacks of hibernate). but therfore th emthod has to determine wether an entity really changed or not.
I stumbled over the dynamic-update property of the <class>-tag in the
hibernate-mapping-definition and I was wondering how this feature works internally, because it somehow must determine if an entity changed.

is there an easy way? how about performance? are both states of the persistent object accessible without querying the db (a) the one on the database and (b) the most actual one of the object before calling hibSess.save(obj)?

thanks alot
marie

Interceptor.onFlushDirty() is called for dirty entities.
Check
http://www.hibernate.org/Documentation/PageViewAndUserTrackingViaInterceptors