Hi,
in my application I have mapped an association (many to many) between the entities "content" and "document".
Now I'd like to implement the concept of "priority" in showing the documents associated with a content in the order I decide in my CMS.
I succeed in passing to the controller the doc ids in the order I want, but when the controller calls the SaveOrUpdate nothing changes in the order of the documents stored on database.
I think it happens because the objects in the session are the same, I only changed the order of their priority.

In my log there are these rows:
16:04:37 DEBUG Cascade - cascade ACTION_SAVE_UPDATE for collection: com.XXXX.contentDocuments
16:04:37 DEBUG CascadingAction - cascading to saveOrUpdate: com.XXXX.Document
16:04:37 DEBUG AbstractSaveEventListener - persistent instance of: com.XXXX.Document
16:04:37 DEBUG DefaultSaveOrUpdateEventListener - ignoring persistent instance
16:04:37 DEBUG DefaultSaveOrUpdateEventListener - object already associated with session: [com.XXXX.Document#10]

I use Hibernate 3.2.

Are there some settings or configuration to force the objects to be saved ?

Thanks.
MB

Hibernate uses automatic dirty checking, which means that all you
have to do is to commit your transaction. Hibernate will detect and save changes to the database automatically. A typical unit of work is like this:

1. begin transaction: tx = session.beginTransaction();
2. load some objects: obj = session.get(...);
3. update some properties: obj.setValue(...);
4. commit the transaction: tx.commit();

There are a few possible things that causes updates to not be written to the database. For example, a property mapped with update="false" or a collection mapped with inverse="true".

Things get more complex if you add long-running conversations, which uses different sessions for loading and committing. There is a good document about this on the Hibernate wiki: http://www.hibernate.org/42.html

To help you with your problem it would be nice to see some code and mapping documents.

In my application I use Spring+Hibernate, so the transaction management is handled by Spring.
I use DAO for adding, getting and setting my properties.
In my case I have the Content entity having a Set of Documents (mapped through an "@hibernate set").

I think that I could use an attribute "priority" added to the relation content/document (mapped in the table content_document, now in in there are in relation the keys of tables content and document).
I think to use this attribute to store the priority when saving the association content/document and use it later for sort my documents when showing.

But how can I map in Hibernate this attribute "priority" as a relationship attribute ?

Thanks.
MB

Yes, I did it.
I added a field "priority" to the relationship table between content and document.

I modified the annotation in my java class for the content-document association:

/**
* @hibernate.map table="content_document" cascade="save-update" order-by="priority asc"
* @hibernate.collection-key column="content_id"
* @hibernate.index-many-to-many column="doc_id" class="com.XXXX.Document"
* @hibernate.collection-element column="priority" type="int" not-null="true"
*/

before I used "set" instead of "map".

So I succeed in handling the attribute priority. When I change the priority of the documents, the object in session now changes, so I can save the changes (showing order) even if the objects in session are the same.