;             } */         case Node.ENTITY_NODE :         case Node.NOTATION_NODE:         case Node.DOCUMENT_FRAGMENT_NODE:         case Node.DOCUMENT_TYPE_NODE:             // type is unknown             return null;         case Node.ATTRIBUTE_NODE:{                 if (this.getOwnerElement().getNodeType() == Node.ELEMENT_NODE) {                     return getOwnerElement().lookupNamespaceURI(specifiedPrefix);                  }                 return null;             }         default:{            /*                 NodeImpl ancestor = (NodeImpl)getElementAncestor(this);                 if (ancestor != null) {                     return ancestor.lookupNamespaceURI(specifiedPrefix);                 }              */                 return null;             }          }     }       /**      * 