Polymorphic Query

Locomotyphus · **Joined:** Mon Oct 09, 2006 4:14 am **Posts:** 1

i do have an inheritance tree of 3 classes: subject, person and organisation. subject is my abstract superclass whereas person and organisation do inherit from subject and are concrete classes.

i have mapped this classes in hibernate 3.1.3 using the table-per-subclass strategy. now i want to fetch all persons and organisations using the criteria query api. i used

Code:

DetachedCriteria.forClass(Subject.class);

this criteria returns to me instances of subject, person and organisation (i made subject non-abstract meanwhile).

my question is: how do i have to conifg hibernate to return me only persons and organisations and to ommit subjects?

here the mapping i use as an example:

Code:

<hibernate-mapping package="com.example">
   <class name="Subject" table="subject">
      <id name="id" type="integer" column="subject_id">
         <generator class="seqhilo">
            <param name="sequence">bip_domain</param>
            <param name="max_lo">100</param>
         </generator>
      </id>
      <joined-subclass name="Person" table="person">
         <key column="subject_id"/>
      </joined-subclass>
      <joined-subclass name="Organisation" table="organisation">
         <key column="subject_id"/>
      </joined-subclass>
   </class>
</hibernate-mapping>

any suggestions?

thx in advance, Gaetano

scesbron · **Joined:** Thu Sep 04, 2003 8:23 am **Posts:** 368

How can you have Subject instances as Subject is abstract ?