joined-subclass question with the "class" property

tcollins · **Posted:** Tue Feb 17, 2004 12:48 pm

I have an AbstractFish object with two joined subclasses Shark and Trout. See the mapping below. (Note: these are just test classes. :)

When I run the following HQL query....
from AbstractFish f where f.id = 1
...everything works out fine, so I am fairly confident that my mappings are correct.

When I run this HQL query...
from AbstractFish f where f.class = com.matrix.bo.Shark
nothing is returned. I do not get an error, but my object is not returned and I know I have data, because I can load the object using a different query.

I have a similar example that uses the table-per-hierarchy with discriminators and the "class" attribute works fine with similar queries.

Question) Does the special attribute "class" in the hibernate query language not work for joined-subclass?

Code:

<hibernate-mapping>
    <class
        name="com.matrix.bo.AbstractFish"
        table="Fish"
        dynamic-update="false"
        dynamic-insert="false"
    >

        <id
            name="id"
            column="Fish_ID"
            type="int"
            unsaved-value="0"
        >
            <generator class="native">
            </generator>
        </id>

        <property
            name="color"
            type="string"
            update="true"
            insert="true"
            column="Color"
            length="70"
            not-null="true"
            unique="false"
        />

        <property
            name="name"
            type="string"
            update="true"
            insert="true"
            column="Name"
            length="50"
            not-null="true"
            unique="false"
        />

        <!--
            To add non XDoclet property mappings, create a file named
                hibernate-properties-AbstractFish.xml
            containing the additional properties and place it in your merge dir.
        -->

        <joined-subclass
            name="com.matrix.bo.Shark"
            table="Shark"
            dynamic-update="false"
            dynamic-insert="false"
        >
        <key
            column="Fish_ID"
        />
        <property
            name="toothSize"
            type="string"
            update="true"
            insert="true"
            column="ToothSize"
            length="35"
            not-null="true"
            unique="false"
        />

        </joined-subclass>
        <joined-subclass
            name="com.matrix.bo.Trout"
            table="Trout"
            dynamic-update="false"
            dynamic-insert="false"
        >
        <key
            column="Fish_ID"
        />
        <property
            name="smell"
            type="string"
            update="true"
            insert="true"
            column="Smell"
            length="40"
            not-null="true"
            unique="false"
        />

        </joined-subclass>

    </class>

</hibernate-mapping>

michael · **Posted:** Tue Feb 17, 2004 12:55 pm

I think it works only for normal subclasses so far.

emmanuel · **Posted:** Tue Feb 17, 2004 2:16 pm

.class is a keyword to retrieve the discriminator

tcollins · **Posted:** Tue Feb 17, 2004 2:39 pm

Ok. Thanks for the quick responses!