spring mvc向不同的域对象共享数据的方式

说的就是如何把后端的数据携带到页面
一、放入request域
向页面中带数据的四种方式
1.ModelAndView
2.Model
3.ModelMap
4.Map
5.使用ServletAPI向request域对象共享数据
1、ModelAndView的方式
@GetMapping(“/abc”)RequestMapping
public ModelAndView testModel(@RequestParam(“name”) String name) {
User user = new User(“liming”, “bjing”);
ModelAndView modelAndView = new ModelAndView(“/index.jsp”);
modelAndView.addObject(“name”, name);
modelAndView.addObject(“msg”, “aaa”);
modelAndView.addObject(“user”, user);
return modelAndView;
}
2、modelMap的方式
@GetMapping(“/abc1”)
public String testModel1(@RequestParam(“name”) String name, ModelMap modelMap) {
User user = new User(“ModelMap携带数据”, “bjing”);
modelMap.addAttribute(“user”, user);
return “index.jsp”;
}
3、Model的方式
@GetMapping(“/abc2”)
public String testModel2(@RequestParam(“name”) String name, Model model) {
User user = new User(“model携带数据”, “bjing”);
model.addAttribute(“user”, user);
return “index.jsp”;
}
4、map的方式
@GetMapping(“/abc3”)
public String testModel3(@RequestParam(“name”) String name, Map map) {
User user = new User(“Map携带数据”, “bjing”);
map.put(“user”,user);
return “index.jsp”;
}

	5、使用ServletAPI向request域对象共享数据
	@GetMapping("/abc4") 
	public String testModel4(HttpServletRequest request) {
		User user = new User("request携带数据", "bjing");
		requset.setAttribute("user",user);
		return "index.jsp";
	}

二、向session域共享数据
@RequestMapping(“/abc5”)
public String testSession(HttpSession session){
session.setAttribute(“testSessionScope”, “hello,session”);
return “index.jsp”;
}

三、向application域共享数据
@RequestMapping(“/abc6”)
public String testApplication(HttpSession session){
ServletContext application = session.getServletContext();
application.setAttribute(“testApplicationScope”, “hello,application”);
return “index.jsp”;
}