Session的创建

@Controller
@SessionAttributes(value = "Save")
@RequestMapping("/")
@ResponseBody
public class pageController {

    //通过自带的域对象requsert获取session
    @RequestMapping("fun3")
    public void fun3(HttpServletRequest request){
        HttpSession session = request.getSession();
        session.setAttribute("ss","44");
        System.out.println(session);
    }
    @RequestMapping("fun4")
    public Object fun4(HttpServletRequest request){
        HttpSession session = request.getSession();
        Object ss = session.getAttribute("ss");
        System.out.println(session);
        return ss;
    }

    //springboot自带注解创建session
    @RequestMapping("fun1")
    public void  fun1(ModelMap modelMap){
        modelMap.addAttribute("Save","共享的数据");
        System.out.println("第一请求完成");
    }

    @RequestMapping("fun2")
    public String fun2(@ModelAttribute("Save") String save){
        System.out.println("save="+save);
        System.out.println("第二次请求完成");
        return save;
    }

}