I have a client that is talking to a webservice that exposes a hibernate-based app, and I am unsure how to proceed about propagating id fields after they're set by session.save(persistentObj).


If client and hibernate were on same vm I could do the following:

Persistent newObj = new Persistent(); //id is null
hibersession.saveOrUpdate(newObj);

//now newObj's id is != null
//do some client-related work on same instance


But, if client and backend run on separate VMs and communicate via an axis web service we have:

//client side code
Persistent newObj = new Persistent(); //id is null
gui.displayWidgetFor(newObj);


//some time later
Persistent newInstanceOfObj = webservice.saveOrUpdate(newObj); //ws creates new instance but I need to keep using newObj

//so I try to simply copy field value
newObj.setId(newInstanceOfObj.getId());

//some time later
webservice.saveOrUpdate(newObj);

//but Hibernate complains:
Exception: org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session: [common.TemplateLibrary#65536]|#]

What can I do?


Hibernate version:3.0.5

Mapping documents:

Code between sessionFactory.openSession() and session.close():

Full stack trace of any exception that occurs:

Name and version of the database you are using:

The generated SQL (show_sql=true):

Debug level Hibernate log excerpt:

I think you need to use a merge in this case.

for last step...to update some time later... do

instead of


from hibernate docs...

I currently save/update using session.saveUpdate(). Your suggestion makes sense, but seems like merge() is strictly an insert. what if the subroutine has to be robust enough to handle both new saves and merges? should I change to?:

public saveMyOBject(Persistent obj)
{

if(session.contains(obj))
{
session.merge(obj);
}
else
{
session.save(obj);
}


thanks

Actually from the API docs for merge...



I haven't tried it but, I'd say it handles it for you. Hibernate rocks!