docs: public static void addOrSetAttribute(final AttributesImpl atts, final String uri, final String localName,
              final String qName, final String type, final String value) {
          final int i = atts.getIndex(qName);
          if (i != -1) {
              atts.setAttribute(i, uri, localName, qName, type, value);
          } else {
              atts.addAttribute(uri, localName, qName, type, value);
          }
      }