public IHierarchicalSchemaNode getTopNode() {
   return new XHierarchicalSchemaNode(m_delegate.thingNode());
 }
  public ISchemaNode getNode(INamedConcept clazz) {

    return new XHierarchicalSchemaNode(
        m_delegate.getNodeFor(KAON2Manager.factory().owlClass(clazz.getUri())));
  }
 public IHierarchicalSchemaNode getBottomNode() {
   return new XHierarchicalSchemaNode(m_delegate.nothingNode());
 }