hibernate inserts null for many-to-one association

fhimpe · **Joined:** Thu Sep 25, 2003 11:00 am **Posts:** 2

Hi,

I've got a class Actor and a class File. Each file is opened by one Actor, while an Actor can open multiple Files. Here are parts of the mapping files for both classes:

Code:

<class name="Actor" table="actors">
               <id name="id" column="id" type="long">
                    <generator class="sequence">
                            <param>actors_id_seq</param>
                    </generator>
               </id>
               <property name="firstName" column="firstname" type="string" />
               <property name="lastName" column="lastname" type="string" />
</class>

Code:

<class name="File" table="file">
               <id name="id" column="id" type="long">
                    <generator class="sequence">
                            <param>file_id_seq</param>
                    </generator>
               </id>
               <property name="dateClosing" column="date_closing"/>
               <many-to-one name="openedBy" column="opened_by" class="be.arafox.sheria.business.Actor"/>
</class>

I get an Actor object from the DB (PostgreSQL 7.2), using the find-method, and use the method setOpenedBy(Actor actor) to link it to the File object. Now when I save the File object, it says i'm trying to assign null to the column opened_by. It seems there is a problem on the mapping layer, but I have no idea what. Somebody could hive me hint? I'm using Hibernate 1.1.

emmanuel · **Posted:** Mon Oct 27, 2003 12:25 pm

http://www.hibernate.org/116.html#A6
I'm having trouble with a bidirectional association.

When you update a bidirectional association you must update both ends.

parent.getChildren().add(child);
child.setParent(parent);