Hibernate CompositeUserType for immutable object

Question

I'm creating a CompositeUserType in hibernate to map EAST and NORTH fields to a Coordinate object. At present my Coordinate object is immutable, and I'd like to keep it that way if possible.

I've written my nullSafeGet, pulling the coordinates from the ResultSet and calling the constructor:

@Override
public Object nullSafeGet(ResultSet rs, String[] names,
            SessionImplementor session, Object owner)
            throws HibernateException, SQLException {
    Integer easting = (Integer)Hibernate.INTEGER.nullSafeGet(rs, names[0]);
    Integer northing = (Integer)Hibernate.INTEGER.nullSafeGet(rs, names[1]);
    if(easting==null || northing==null)
        return null;
    return new Coordinate(easting, northing);
}

I don't know what to do with setPropertyValue, which seems to want to set the coords one at a time. It is possible to instantiate an immutable object with CompositeUserType, or I am trying to do the impossible?

(Also trying to work out what to do about Hibernate.INTEGER being deprecated, but one thing at a time...)

Answer 1

setPropertyValue() is never called if isMutable() returns false, so you can throw UnsupportedOperationException from it.