code: public static IntSet getIntParameters (
          HttpServletRequest req, String name, String invalidDataMessage)
          throws DataValidationException
      {
          IntSet ints = new ArrayIntSet();
          String[] values = req.getParameterValues(name);
          if (values != null) {
              for (int ii = 0; ii < values.length; ii++) {
                  if (!StringUtil.isBlank(values[ii])) {
                      ints.add(parseIntParameter(values[ii], invalidDataMessage));
                  }
              }
          }
          return ints;
      }
docs: Fetches all the values from the request with the specified name and converts them to an
  IntSet.  If the parameter does not exist or is not a well-formed integer, a data validation
  exception is thrown with the supplied message.