Problem with parent/child relationship

FesterWim · **Posted:** Tue Jan 06, 2004 6:06 am

Hi,

I have this class:

Code:

public class Vak
{
    private String _id;
    private String _name;
    private List _subVakken;
    private Vak _parentVak;
}

with corresponding get and set methods for all fields. The List _subVakken contains again "Vak"-objects where this Vak is then in the field _parentVak.

I have this hibernate mapping:

Code:

<hibernate-mapping>
 <class name="com.misoftware.reports.models.Vak" table="VAK">
  <id name="id" type="string" unsaved-value="null">
  <column name="id" not-null="true"/>
  <generator class="uuid.hex"/>
 </id>

 <property name="name" type="string"/>
 <bag name="subVakken" inverse="true" lazy="true">
  <key column="parentVak_id"/>
  <one-to-many class="com.misoftware.reports.models.Vak"/>
 </bag>
<many-to-one name="parentVak" class="com.misoftware.reports.models.Vak" column="parentVak_id"/>
 </class>
</hibernate-mapping>

This does not seem to work. The List _subVakken is empty if I read the object back from hibernate if I close and re-open the session before reading.

Can someone tell me what is wrong with my mapping?

When I save the object I only call session.saveOrUpdate on the parent "Vak" (the field _parentVak is null in that case)

regards,

Wim

emmanuel · **Posted:** Tue Jan 06, 2004 12:10 pm

http://www.hibernate.org/hib_docs/reference/html_single/#parent-child
Read it carefully

FesterWim · **Posted:** Tue Jan 06, 2004 12:21 pm

Looks like the cascade attribute is what I was missing. Thank you for your help, I'll try it out!