All,

I want to create a many-to-many mapping with an order so I can map images to categories and also specify the order of the images in the categories.

My example mapping files

Category.hbm.xml:
<hibernate-mapping>

<class name="Category"
table="CATEGORY"
mutable="true">

<cache usage="transactional"/>

<id name="id" column="CATEGORY_ID"
unsaved-value="null">
<generator class="native"/>
</id>

<property name="name"
column="CATEGORY_NAME"
update="true"
length="100"/>

</class>

</hibernate-mapping>

Image.hbm.xml
<hibernate-mapping>

<class name="Image"
table="IMAGE"
mutable="true">

<cache usage="transactional"/>

<id name="id" column="IMAGE_ID"
unsaved-value="null">
<generator class="native"/>
</id>

<property name="name"
column="IMAGE_NAME"
update="true"
length="100"/>
</class>

</hibernate-mapping>


and my table schema should become like this:

IMAGE
-----
IMAGE_ID
IMAGE_NAME


CATEGORY
-------
CATEGORY_ID
CATEGORY_NAME


IMAGE_CATEGORY
-------------
IMAGE_ID
CATEGORY_ID
ORDER

Who has a suggestion or example for me?
Thanks in advance.
Niels

I guess you can have ImageCategoryLink class that will be simple class like
Class ImageCategoryLink {
Category category;
Image image;
}

And then simply retrieve necessary images by HQL like
“from ImageCategoryLink icl where icl.category.id = ? order by icl.image.name”
or
“from ImageCategoryLink icl order by icl.category.name , icl.image.name”
or
“from ImageCategoryLink icl order by icl.image.name , icl.category.name ”


and mapping of ImageCategoryLink is simple many-to-one
http://www.hibernate.org/hib_docs/v3/re ... -manytoone