code: public Date getLastModified(String filename)
          throws IOException, ServerException {
          if (filename == null) {
              throw new IllegalArgumentException("Required argument missing");
          }
          Command cmd = new Command("MDTM", filename);
          Reply reply = null;
          try {
              reply = controlChannel.execute(cmd);
          } catch (FTPReplyParseException rpe) {
              throw ServerException.embedFTPReplyParseException(rpe);
          } catch (UnexpectedReplyCodeException urce) {
              throw ServerException.embedUnexpectedReplyCodeException(
                                  urce,
                                  "Server refused changing transfer mode");
          }
  
          if (dateFormat == null) {
              dateFormat = new SimpleDateFormat("yyyyMMddHHmmss");
              dateFormat.setTimeZone(TimeZone.getTimeZone("GMT"));
          }
  
          try {
              return dateFormat.parse(reply.getMessage());
          } catch (ParseException e) {
              throw ServerException.embedFTPReplyParseException(
                       new FTPReplyParseException(
                              0,
                              "Invalid file modification time reply: " + reply));
          }
      }
docs: Returns last modification time of the specifed file.
  
  @param     filename filename get the last modification time for.
  @return    the time and date of the last modification.
  @exception ServerException if the file does not exist or
  an error occured.