RequestContext requestContext = new RequestContext(request);
这个在SPRING 5.0 里面说没有此构造函数 TOMCAT 8.0 +JDK 9.0+SPRING 5.0
该怎么办呢？

public String login(@ModelAttribute @Validated User user,Model model,HttpServletRequest request)
{
if(user.getLoginname()!=null && user.getLoginname().equals("fkit")
&& user.getPassword()!=null && user.getPassword().equals("123456"))
{
//从后台代码获取国际化信息username
RequestContext requestContet = new RequestContext(request);