我们用不同的方式来实现数据的 传递:
package com.lagou.edu.controller;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
import java.util.Date;
import java.util.Map;
/**
* @author lyj
* @Title: DemoController
* @ProjectName springmvc-demo
* @Description: TODO
* @date 2020/6/9 21:21
*/
@Controller
@RequestMapping("/demo")
public class DemoController {
/**
* http://localhost:8080/demo/handle01
*/
@RequestMapping("/handle01")
public ModelAndView handle01(){
Date date=new Date();
ModelAndView modelAndView=new ModelAndView();
modelAndView.addObject("date",date);
modelAndView.setViewName("success");
System.out.println("modelAndView----"+modelAndView.getClass());
return modelAndView;
}
/**
* http://localhost:8080/demo/handle02
*/
@RequestMapping("/handle02")
public String handle02(ModelMap modelMap){
Date date=new Date();
modelMap.addAttribute("date",date);
System.out.println("modelMap------"+modelMap.getClass());
return "success";
}
/**
* http://localhost:8080/demo/handle03
*/
@RequestMapping("/handle03")
public String handle03(Model model){
Date date=new Date();
model.addAttribute("date",date);
System.out.println("model-----"+model.getClass());
return "success";
}
/**
* http://localhost:8080/demo/handle04
*/
@RequestMapping("/handle04")
public String handle04(Map<String,Object>map){
Date date=new Date();
map.put("date",date);
System.out.println("map------"+map.getClass());
return "success";
}
}
下面我们来看输出结果:
modelAndView----class org.springframework.web.servlet.ModelAndView
modelMap------class org.springframework.validation.support.BindingAwareModelMap
model-----class org.springframework.validation.support.BindingAwareModelMap
map------class org.springframework.validation.support.BindingAwareModelMap
说明他们最后都是执行的BindingAwareModelMap
ModelMap:
LinkedHashMap是jdk里面的 package java.util;
Model:
Map:
Map也是java.util下面的
BindingAwareModelMap