Hello

I have a many-to-many relationship via a join table.

let's they the represent books and authors.

when I have a book object and get all the authers with
book.getAuthors()
I want an ordered List. when using a Query I can call the list() method to
give me a List. but in the mapping file I have to use the <set> mapping (I couldn't get
an example using <list> to work. if this can be done let me know).

when I get the list from the database and put it into the authors property of the book
object I loose the ordering because this is a Set.
I can use a tree set and then I will have the ordering.

but let's say I want to order the authors on some specific criteria.
How can I do this ? can I store the ordering information in the join table in an extra column ?
that would probably work, but how do I access this column ?
or maybe I can insert them into a specific order into the join table and then retrieve them in
the same order.

I hope this is not to confusing. maybe I am just thinking to complicated.

any help appreciated.

best wishes

Claus

I have successfully used the list for one-to-many association like this

<list name="childNodes" cascade="all" inverse="true">
<list-index column="LISTORDER"/>
<one-to-many class="childNodeClass"/>
</list>

I am not sure but I think this should work for many-to-many also.

else go through this link

http://www.hibernate.org/hib_docs/v3/re ... tions.html

it mentions that you can provide sort or order-by attributes in collection mapping to sort the collection elements.

Hope this help!

You can use list, but you can achieve the same with set also.

<set name="tags" table="PERSON_TAGS" order-by="lower(LANGUAGE) ASC" inverse="true">
<key column="PERSON_ID"/>
<many-to-many column="TAG_ID" class="xxx.Tag"/>
</set>

So here the set of tags will be ordered by column LANGUAGE.

Hope that helps.
Thanks