code: public static String getFullURL(HttpServletRequest request) {
          if (request == null) {
              return null;
          }
          String url = request.getRequestURL().toString();
          String QueryString = request.getQueryString();
          if ((QueryString != null) && (QueryString.length() > 0)) {
              url = url + "?" + QueryString;
          }
          return url;
      }
docs: 获得整个url,如http://www.weamea.com/music/index.jsp?id=4342
  
  @param request
  请求request
  @return url