code: public static String[] getRDNAttributes(String dn) {
          String rdnstr = getRDN(dn);
          StringTokenizer st = new StringTokenizer(rdnstr.toLowerCase(), "+");
          List<String> list = new ArrayList<String>();
          while (st.hasMoreTokens()) {
              String rdn = st.nextToken();
              int index = rdn.indexOf('=');
              if (index > -1) {
                  list.add(rdn.substring(0, index));
              }
          }
          return list.toArray(new String[0]);
      }
docs: Return an array of RDN attributes of the given DN in lower case form.
  
  @param dn
  @return