How to refresh persistent object in a session ?

tgi2 · **Joined:** Thu May 19, 2011 5:27 am **Posts:** 4

Hi All

How can I refresh the persistent objects in a session, so that the object is updated with the data in the database ?

The problem is, I have 2 applications.
The 1st reads the entities with:

Code:

var Users session.Query<User>();

Then the 2nd reads the entities with the same statement and adds more datasets:

Code:

var Users2 session.Query<User>();
User user = new User("Hans", "Muster");
Users2.Add(user);
session.SaveOrUpdate(Users2);

But then, when the first application wants to add more datasets, I get the following error:
"a different object with same identifier value was already associated with the session"

I tried everything like:

Code:

session.Evict(Users)
Users = Users session.Query<User>();
Users.Add(......)
session.SaveOrUpdate(Users2);

or:

Code:

Users = Users session.Query<User>();
session.Merge(Users);
Users.Add(......)
session.SaveOrUpdate(Users2);

or:

Code:

session.Flush();
Users = Users session.Query<User>();
Users.Add(......)
session.SaveOrUpdate(Users2);

without success.

However, I could close the session and reopen it, but I don't want to do this as I want to use lazy loading which does not allow to close a session.

So please, how can a refresh or better reread data from the database into a persistent object, so that this error exception can be avoided.

Thank you for your hints
Tom

manimoor · **Joined:** Wed Aug 10, 2011 4:45 am **Posts:** 3

Hi...Persistent objects exist in the database, and Hibernate manages the persistence for persistent objects.If fields or properties
change on a persistent object, Hibernate will keep the database representation up-to-date.

Hibernate provides a mechanism to refresh persistent objects from their database representation.Use one of the refresh()
methods on the Session interface to refresh an instance of a persistent object, as follows:

public void refresh(Object object) throws HibernateException
public void refresh(Object object, LockMode lockMode) throws HibernateException