如果可能缺少请求参数，请用标记
required = false：
public ModelAndView showTestPage(@RequestParam("firstInstanceId") String id1, @RequestParam(value = "secondInstanceId", required = false) String id2, HttpSession session) { ...}
如果可能缺少请求参数，请用标记
required = false：
public ModelAndView showTestPage(@RequestParam("firstInstanceId") String id1, @RequestParam(value = "secondInstanceId", required = false) String id2, HttpSession session) { ...}名师互学网 版权所有 (c)2021-2022 ICP备案号：晋ICP备2021003244-6号
