/**
   * Add a referral to this group
   *
   * @param flavor Flavor
   * @param url URL
   * @param date Date
   * @param total Total number of hits
   */
  public void addReferer(String flavor, String url, Date date, int total) {
    if (_groups.containsKey(url)) {
      BlogReferer br = (BlogReferer) _groups.get(url);
      br.setLastReferral(date);
      br.setCount(total);
    } else {
      _groups.put(url, new BlogReferer(flavor, url, date, total));
    }

    _grouptotal += total;
  }