I have nested Many to One relationships (just object references)
and they are null.


a Document object has a Employee object which has a Department object.
(many others too)

I can load it, and view it, but updates fail.
I am not certain if there is something i have to do special for nested many to one relationships.

any hints?

thanks
-fred

Fred, post your mappings of your Department, Document and Employee, in particular your one-to-many relationships. As well as the code you use for loading and updating.

That'll make things a lot easier for the Hibernate team to help you.

-G

file DocumentsTO.hbm.xml---------
<hibernate-mapping>
<class name="test.documents.data.DocumentsTO" table="documents" >

<id name="documentID" type="string" unsaved-value="null">
<column name="Document_ID" sql-type="VARCHAR(36)" not-null="true"/>
<generator class="uuid.hex"/>
</id>

<property name="documentUrl" column="Document_Url" type="string" not-null="true"/>

<many-to-one name="employeesTO" column="Employee_ID" class="test.employees.data.EmployeesTO"
not-null="true" cascade="none" outer-join="true" insert="false" update="false">
</many-to-one>
<property name="updateDate" column="Update_Date" type="date" not-null="true"/>

</class>
</hibernate-mapping>
------------
file EmployeesTO.hbm.xml--------
<hibernate-mapping>
<class name="test.employees.data.EmployeesTO" table="employees" >

<id name="employeeID" type="string" unsaved-value="null">
<column name="Employee_ID" sql-type="VARCHAR(36)" not-null="true"/>
<generator class="uuid.hex"/>
</id>

<property name="firstName" column="First_Name" type="string" not-null="true"/>

<property name="lastName" column="Last_Name" type="string" not-null="true"/>

<property name="title" column="Title" type="string" not-null="true"/>

<property name="manager" column="Manager" type="string" not-null="true"/>

<many-to-one name="departmentsTO" column="Department" class="test.departments.data.DepartmentsTO"
not-null="true" cascade="none" outer-join="true" insert="false" update="false">
</many-to-one>
<property name="dateHire" column="Date_Hire" type="date" not-null="true"/>

</class>
</hibernate-mapping>
----------
file DepartmentsTO.hbm.xml-------
<hibernate-mapping>
<class name="test.DepartmentsTO" table="departments" >

<id name="department" type="string" unsaved-value="null">
<column name="Department" sql-type="VARCHAR(64)" not-null="true"/>
<generator class="assigned"/>
</id>

<property name="departmentHead" column="Department_Head" type="string"/>

<property name="parentDepartment" column="Parent_Department" type="string"/>

<property name="description" column="Description" type="string"/>

</class>
</hibernate-mapping>
------------

Documents (m-to-1) Enp (m-to-1) Departments.

here is an example update method (all are same)
public DepartmentsTO update(DepartmentsTO to) {
HibernateTemplate hibernateTemplate = new HibernateTemplate(this.sessionFactory);
hibernateTemplate.saveOrUpdate(to);
return to;
}

thanks,
-fred

Offhand, I see you don't have any collection defined in your "one" side of the one-to-many's. i.e.

Something like this in DepartmentsTO:


I used bag, but you can use set, or another collection type.

This tells your parent object, that it has a 1-M relationship with your child, as well as the link you already have in your child (telling the children who the parent is).

Check out Chapter 5 in the reference document for information on various Collections, and Chapter 8 for Parent-Child relationships.

I'm not sure if there's a problem in your code, perhaps one of the Hibernate guys can check that.

Hope that helps.

-G

thanks,
do i have to have the other side of the relationship setup? (i don't think i want it, if i don't need it)

-f

is anyone just using many to one object refernces like i am
(and don't want to use the bidirectional features)

this should be very simple. what am i missing?
thanks,
-Fred

Of course. It is trivial. Just don't map your associations with

insert="false" update="false"

:)