code: public static String urlDecode(String input) {
          try {
              return URLDecoder.decode(input, "UTF-8");
          } catch (UnsupportedEncodingException ex) {
              throw new AssertionError("UTF-8 not supported", ex);
          }
      }
docs: URL decodes an input String using the UTF-8 character set
  (IExtensionHelpers class uses LATIN-1)
  
  @param input The String to decode
  @return The URL-decoded String