Hello.

Hibernate's examples are many... but nevertheless, i did find anything I want...

I'm trying top build a very simple relationship with two objects :
- orders, with an assigned string id
- order items, whose primary key is the order id and a number

To make it as simple as possible, i use a simple composite association like this for the order mapping :

<list
name="itemList"
table="ORDER_ITEMS"
lazy="false"
cascade="all">
<key column="ORDER_ID" />
<list-index column="ITEM_NUMBER" />
<composite-element class="OrderItem">
<property
name="description"
length="32" />
</composite-element>
</list>

And it works as expected : items are inserted, with a foreign order-id key and generated index; they are updated and deleted too when the order list changes.

Now, i'd like to add a return path from the order item to its order : client classes that handle items need to get back to the containing order... If i'm not mistaken, this could be done in other cases using a "many-to-one" on an entity.

How can i add this to my order item ? Should i change it all to use two entities ? I've also tried it, but the item composite key is tedious, and doesn't seem to support any form of automatic generation...

Thanks for your help.

--
Ephemeris Lappis

You can do it as follows:


As HiA states, true bidirectional navigation is not possible in this case. You cannnot retrieve an OrderItem independently. For that you would need to use entities.

Hope this helps!
Urs

First, thanks for your answer !

I've tested the parent attribute, and it works just as i wanted.
Now, if i need to link more data on my order item, say the 'many' part of the relationship, a pure entity is really a better way. So i've tried alternative way to declare two entities. In this case, item the composite key must be handled by the application : declare it, of course, but also generate values too. I've not found any way to make the item number handled according to the list elements.

Another idea ?

Thanks again.