获取HttpServletRequest中网址信息

//http://localhost/user/login?username=123&password=1231324
StringBuilder query = new StringBuilder(request.getRequestURL()).append("?");
 if ("GET".equals(request.getMethod())) {
     //get请求
     query.append(request.getQueryString());
 } else if ("POST".equals(request.getMethod())) {
     //post请求
     if (!StringUtils.isEmpty(query.toString())) {
         Map map = request.getParameterMap();
         if (map != null) {
             int size = map.size();
             System.out.println(size);
             for (Map.Entry entry : map.entrySet()) {
                 query.append(entry.getKey()).append("=").append(entry.getValue()[0]);
                 if ((--size) != 0) query.append("&");
             }
         }
     }
 }