Apologies if the simplicity of my question offends, but I'm going round in circles, and I'd like to know if what I'm trying to achieve is actually possible.

My domain consists of a "person" object, and a "baggage" object. A person can have zero or more items of baggage, in a set. Baggage can also exist outside of a person.

I wish to create a person with a number of baggage objects, then save the person, which in turn will save all the new baggage objects.

I have played with a number of approaches, where hibernate either complains that it tries to update the nonexistent baggage objects, neglects the foreign keys, or my final problem, where the information appeared to be stored but would then not come back out. All user errors I'm sure.

In short, can I save a parent object, which in turn saves all the children objects. Where the child objects also have unique id's so they can be accessed individually? I'm hoping that the child object doesn't have to contain a reference to the parent. Can anyone point me to an example of this? I have found many examples that don't quite seem to cover my situation.

Hibernate version: 2.1

Mapping documents:
<hibernate-mapping>
<class name="airline.hibernate.Baggage" table="BAGGAGE">

<id name="baggageId" type="java.lang.Integer" column="baggage_id" unsaved-value="null" >
<generator class="sequence">
<param name="sequence">BAGGAGE_ID_SEQ</param>
</generator>
</id>

<many-to-one name="personId" column="person_id" class="airline.hibernate.Person"/>

<property name="description">
<column name="description" sql-type="varchar2(1000)" not-null="true"/>
</property>
</class>
</hibernate-mapping>


<hibernate-mapping>
<class name="airline.hibernate.Person" table="PERSONS">
<id column="PERSON_ID" name="personId" type="java.lang.Integer">
<generator class="sequence">
<param name="sequence">PERSON_ID_SEQ</param>
</generator>
</id>

<property
name="firstName"
type="java.lang.String"
column="FIRST_NAME"
not-null="true">
</property>
<property
name="lastName"
type="java.lang.String"
column="LAST_NAME"
not-null="true">
</property>

<set name="baggage" cascade="all">
<key column="person_id"/>
<one-to-many class="airline.hibernate.Baggage"/>
</set>

</class>
</hibernate-mapping>

Name and version of the database you are using:
Oracle 9i

Please read http://www.hibernate.org/hib_docs/reference/en/html/example-parentchild.html, parent-child relationships are pretty well explained there.

Thanks for the prompt reply.

I have a follow up query.

In the reference you mentioned and all examples I have seen, bidirectional relationships are used. However, I did note that in the hibernate docs covering collections http://www.hibernate.org/hib_docs/reference/en/html/collections.html#collections-onetomany , it was mentioned that if you relax the database constraints you may get away with not using bidirectional relations.

Is this a possibility or will I be severely limiting my options by trying to avoid bidirectional relationships?

I am concerned because ultimately in my scenario, my objects will be marshalled from xml and I may not be able to re-create bidirectional relationships.

Many thanks