@Override
    public void addAttribute(final @NonNls String key, final String nsPrefix, final String nsURI, final String value, final String type)
        throws Exception {
      if (myCurrentDepth == 1 && "schema".equals(myCurrentTag)) {
        if ("targetNamespace".equals(key)) {
          myNamespace = value;
        }
        else if ("version".equals(key)) {
          myVersion = value;
        }
      }
      else if ("element".equals(myCurrentTag)) {
        if (myCurrentDepth < 3 && "name".equals(key)) {
          myTags.add(value);
        }
        else if ("ref".equals(key)) {
          myReferencedTags.add(XmlUtil.getLocalName(value).toString());
        }
      }
    }
@Override
    public void addAttribute(final @NonNls String key, final String nsPrefix, final String nsURI, final String value, final String type)