I have been working several hours on creating a list within a list in hibernate. I have a parent object with a list of children, and each child can have a list associated with it.

Parent table
parentid, (several fields)
From the mapping:
<list name="children" table="child_1" cascade="all">
<key column="parentId"/>
<index column="listIndex"/>
<one-to-many class="test.Child1"/>
</list>

Child 1 table:
id (auto-incremented), parentId (links to parent table), name, description, listIndex
From the mapping:
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
<class name="test.Child1" table="child_1">
<id name="id" column="id" type="long">
<generator class="increment"/>
</id>
<property name="name"/>
<property name="description"/>
<list name="values" table="child_value">
<key column="id"/>
<index column="listIndex"/>
<many-to-many column="value" class="test.Value"/>
</list>
</class>

</hibernate-mapping>
<!-- parsed in 0ms -->

Child 2 table:
id (links to child table's id), value (links to another table), listIndex
(linked from other mapping)

Everything worked fine until I added the id column and third table. I had it more or less working, but was getting hibernate errors every other transaction (problems with all-delete-orphan, which was not solved by clearing the list, and manually deleting the items didn't work either). I would like to implement a double layered list, but I would like to eliminate the "id" column from the first child table. Is there a clean way to do this? Like, for instance, is there any way I could implement the third child to have the link to id and listIndex of the first child table, coupled with a listIndex2 as a composite key of 3?