Grails: domain class mapping (collection of hibernate user types)

Question

I am wondering if is possible to implement following domain model.

Let\'s have a domain class which contains set of intervals (joda time). I can use org.joda.time.contri

Answer 1

I am replying my own question, maybe this answer will be useful for someone.

Until now I have found only one way how to implement given model - by Hibernate XML mapping files:

<hibernate-mapping package="mappingtest">  
    <class name="Activity">  
        <id name="id">  
            <generator class="native"/>  
        </id>  
        <set name="intervals">  
            <key column="activity_id" not-null="true"/>  
            <element type="org.joda.time.contrib.hibernate.PersistentInterval">  
                <column name="startDate"/>  
                <column name="endDate"/>  
            </element>  
        </set>  
    </class>  
</hibernate-mapping>  

and domain class implementation:

class Activity {    
    Long id    
    Set intervals = []

    static constraints = {
    }
}

I also had to move domain class from grails-app/domain to src/groovy directory, otherwise application running failed with (grails-1.3.5):

...
org.hibernate.DuplicateMappingException: Duplicate class/entity mapping mappingtest.Activity
...

Second problem with above implementation I have discovered is that when I turned on scaffolding (for testing purpose) by:

class ActivityController {
    static scaffold = true
    ...
}

showing of created activity failed with error:

Exception Message: No such property: id for class: org.joda.time.Interval Possible solutions: end Caused by: Error evaluating expression [i.id] on line [38]: No such property: id for class: org.joda.time.Interval Possible solutions: end

but manual implementation of getting activities from DB and its showing worked.

Edit: additionally I found solution of scaffolding and DuplicateMappingException issues. They were caused by invalid location of Activity.hbm.xml - package directory structure was missing. Correct location is grails-app/conf/hibernate/mappingtest/Activity.hbm.xml.