(pseudocode)

MyObject ob = hibernate.get(idOfExisting)
hibernate.evict(ob)
ob.setId(0)
hibernate.save(ob)

   BeanPopulatable vetoer = new MyVetoer(session);
   // Deeply replicate the "fromBean" but not the ID's,
   // eagerly fetching as necessary
   Object toBean = HibernateBeanReplicator.dupEntityBean(fromBean, vetoer);

/** Not to populate ID's. */
public class MyVetoer implements BeanPopulatable {
   private SessionFactory sessionFactory;
   
   public MyVetoer(Session session) {
      this.sessionFactory = session.getSessionFactory();
   }
   
   public boolean shouldPopulate(String propertyName, Method readerMethod)
   {
      if (Collection.class.isAssignableFrom(readerMethod.getReturnType()))
         return true;
      // Skip populating if it is an identifier property.      
      Class c = readerMethod.getDeclaringClass();

      if (Enhancer.isEnhanced(c)) {
         // figure out the pre-enhanced class
         c = c.getSuperclass();
      }
      ClassMetadata classMetaData = sessionFactory.getClassMetadata(c);
      return !classMetaData.getIdentifierPropertyName().equals(propertyName);
   }
}

public class MyVetoer implements BeanPopulatable {
    ...
    public boolean shouldPopulate(String propertyName, Method readerMethod)
    {
       ...
       return classMetaData == null || !classMetaData.getIdentifierPropertyName().equals(propertyName);
    }
}

    Object replicateObject = new Object();
    BeanPopulatable vetoer = new MyVetoer(this.hibernateSessionProvider.getSession());
   
    Set setEntityBean = new HashSet();
    Class[] arrayEntityBean = {MySuperClass.class};
    setEntityBean.addAll(Arrays.asList(arrayEntityBean));
   
    Set setProperties = new HashSet();
    String[] arrayProperties = {"onePropertyNameFromMySuperClass", "otherPropertyNameFromMySuperClass"};
    CollectionPropertyName[]  tabCollectionPropertyName =     CollectionPropertyName.createCollectionPropertyNames(MySuperClass.class, arrayProperties);
    setProperties.addAll(Arrays.asList(arrayProperties));
   
    HibernateBeanReplicator replicator = new Hibernate3BeanReplicator()
                                                                    .initVetoer(vetoer)
                                                                    .initCollectionPropertyNameSet(setProperties)
                                                                    .initEntityBeanClassSet(setEntityBean);

    replicateObject = replicator.copy(object);