Hi,

I have a simple question with maybe a not so simple answer:

Is it possible to have nested Collection(s)OfElements?

What I mean is this:


If yes, how would I declare the join column?

I tried using the entity id for the elements collection inside the entity and using the entity id and the element index for the sub elements inside the elements.
However, when deploying this I get a ConcurrentModificationException.

I hope someone can shed some light on this.

Thanks in advance.

Thomas

Yes. Consider the mapping example below.

<class name="Product">
<id name="serialNumber" column="productSerialNumber"/>
<set name="parts">
<key column="productSerialNumber" not-null="true"/>
<one-to-many class="Part"/>
</set>
</class>

<class name="Part">
<id name="serialNumber" column="partSerialNumber"/>
<set name="items">
<key column="partSerialNumber" not-null="true"/>
<one-to-many class="Item"/>
</set>
</class>

Class Product{
private Set<Part> parts;
}

Class Part{
private Set<Item> items;
}

Product
+- elements(Parts)
+- subelements(Items)