Hi everybody,

My problem is very simple :
- I have many objects (Entity class)
- each Entity can be associated with others Entities

Actually, I would like to have a base that looks like :

*********
* Entity *
*********
* id *
* name *
* ...etc...*
* ****** *

***************
* Entities_Links *
***************
* entity_id1 *
* entity_id2 *
* ****** *******

I then write the following hibernate mapping :

<hibernate-mapping>
<class name="Entity" table="ENTITY">
<id name="idBD" column="IDBD">
<generator class="native"/>
</id>

<set name="entities" table="ENTITIES_LINKS">
<key column="IDBD"/>
<many-to-many column="IDBD" class="Entity"/>
</set>
</class>
</hibernate-mapping>


And I get the following error :
Initial SessionFactory creation failed.org.hibernate.MappingException: Repeated column in mapping for collection: Entity.entities column: IDBD


I suppose hibernate is not able to directly create an association from one class to itself.
Then how can this be done ???

Thanxs a lot for your help,
Regards,
Steve

Both your column names in the join table(ENTITIES_LINKS) are the same(IDBD). You need to give a separate name for each of the columns in the table. Make your mapping something like this.