protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        response.setCharacterEncoding("UTF-8");
        response.setContentType("text/html;charset=utf-8");

        String method = Util.nullToString(request.getParameter("method"));
        if("viewAllGSs".equalsIgnoreCase(method)){//for view all admin user page
            doViewAllGSs(request, response);
        }else if("editGS".equalsIgnoreCase(method)) {//for view special user page
            doEditGS(request, response, false);
        }else if("updateGS".equalsIgnoreCase(method)) { //for update special user page
            doUpdateGS(request, response);
        }else if("addGS".equalsIgnoreCase(method)) {//for add user page
            doAddGS(request, response);
        }else if("saveGS".equalsIgnoreCase(method)) {//for add user page
            doSaveGS(request, response);
        }else if("delGS".equalsIgnoreCase(method)) {//for add user page
            doDelGS(request, response);
        }else{
            doViewAllGSs(request, response);
        }

    }