Hi There,

I have a question about one-to-one formula.

Let’s say I have domain object and container (org uint) object. Domain has list of containers, but only one is rootContainer. So domain to rootContainer is one-to-one mapping base on container.parent is null. So I’m using one-to-one with formula for this purpose.

<class name=”Domain” …>

  <id name”id” type=”long”>

     <generator class=”native”/>

  </id>

  <one-to-one name=”rootContainer” class=”Container” property-ref=”rootContainer”>

    <formula>id</formula>

    <formula>null</formula>

  </one-to-one>

</class>

<class name=”Container” …>

  <id name”id” type=”long”>

     <generator class=”native”/>

  </id>

  <propperties name”rootContainer” >

     <many-to-one name=”domain” class=”Domain”>

       <column name=”domainid”/>

     </many-to-one>

     <many-to-one name=”parent” class=”Container”>

       <column name=”parentid”/>

     </many-to-one>

  </properties>

  <set name=”children” inverse=”true”>

     <key column=”parentid”/>

     <one-to-many class=”Container” />

  </set>

</class>

I know it doesn’t work, my question is: for two formulas, how can I set domain object for first formula parameter? How can I set null object reference as second formula parameter instead of “null” string?

Any hint will be highly appreciated.

Thanks

Wei