How to add mapping files to SessionFactory after created?

krein · **Joined:** Mon Nov 20, 2006 4:58 am **Posts:** 3

In my project ,we want to empower users to create their own object from our application UI, I know we can use hibernate tools to generate java files, mapping files and even the table in database.

My question is how can I dynamic add these mapping files to SessionFactory after it has been created in runtime without recreated the SessionFactory?

AmRas · **Joined:** Wed Nov 29, 2006 8:45 am **Posts:** 2

I have the same question.. does anyone knows how to solve it?

Any help will be appreciated.

steckemetz · **Posted:** Wed Nov 29, 2006 11:35 am

I think it is not possible,
because of the complex relations of objects already loaded in
a session.

pasha · **Joined:** Sat Nov 27, 2004 4:13 am **Posts:** 137

well, I think you must recreate the sessionfactory, but you can use session factory's mapping metadata...

krein · **Joined:** Mon Nov 20, 2006 4:58 am **Posts:** 3

Create a new class same as Configuration.mapping;
Create a new SessionFactoryImpl just like the given one,change the visibility of identifierGenerators,entityPersisters and classMetadata to public ,then make classMetadata modifiable by remove the unmodifiable wrapper (classMetadata = Collections.unmodifiableMap(classMeta);)

max · **Posted:** Thu Nov 30, 2006 7:41 am

NO!

messing with the state of the sessionfactory is in no way supported or supposed to work!

Your suggested changes is not thread safe plus a dozen other side effects that can be caused by messing with thought to be immutable datastructures.

krein · **Joined:** Mon Nov 20, 2006 4:58 am **Posts:** 3

Thanks a lot for max's comment.

But is that means the only way that can add mappings to sessionFactory at run time is to recreate the sessionFactory at run time?

My question is if I do by that way ,how about the sessions created by the original sessionFactory?

Or maybe i shouldn't use hibernate in this case?

AmRas · **Joined:** Wed Nov 29, 2006 8:45 am **Posts:** 2

Yes, maybe the better option should be don´t use hibernate if you need to add mappings at runtime.

Thanks to krein reply, I started diving in hibernate source code, and actually I can restart sessionFactory hardcore-using new SessionFactoryImpl() constructor (and also changing some attribute access to public).

First of all, I get sure that are no clients using my server.

It works, but it´s very, very slow, and really a dirty solution. But better than restart the entire developement process of my application.