SpringMVC的Contrller控制器层的三种写法详解

电玩女神 2023-06-09 11:24 82阅读 0赞

转载链接：[https://www.cnblogs.com/zjf-1992/p/5736101.html][https_www.cnblogs.com_zjf-1992_p_5736101.html]

**MVC框架是什么**

模型-视图-控制器（MVC）是一个众所周知的以设计界面应用程序为基础的[设计模式][Link 1]。它主要通过分离**模型、视图及控制器**在应用程序中的角色将业务逻辑从界面中解耦。通常，模型负责封装应用程序数据在视图层展示。视图仅仅只是展示这些数据，不包含任何业务逻辑。控制器负责接收来自用户的请求，并调用后台服务（manager或者dao）来处理业务逻辑。处理后，后台业务层可能会返回了一些数据在视图层展示。控制器收集这些数据及准备模型在视图层展示。MVC模式的核心思想是将业务逻辑从界面中分离出来，允许它们单独改变而不会相互影响。

[![format_png][]][format_png 1][![format_png 2][]][format_png 1][![format_png 3][]][format_png 1]

package com.platform.mvc.system.layer.controller.test;
    
    import java.util.ArrayList;
    import java.util.HashMap;
    import java.util.List;
    import java.util.Map;
    
    import javax.servlet.http.HttpServletRequest;
    
    import org.apache.catalina.connector.Request;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    import org.springframework.web.bind.annotation.RequestParam;
    import org.springframework.web.bind.annotation.ResponseBody;
    import org.springframework.web.servlet.ModelAndView;
    
    @Controller
    @RequestMapping("/user")
    public class userCtroller {
        
        //方式一：String
        @RequestMapping("test")
        public String list(Map<String, Object> map){
            创建一个数组对象
            List<Map<String, Object>> userList = new ArrayList<Map<String, Object>>();
            for (int i = 0; i <10; i++) {
                //存储对象map<K, V>
                Map<String, Object> map1 = new HashMap<String, Object>();
                map.put("name", "HelloKitty"+i);
                map.put("age", i);
                map.put("dept", "技术部"+i);
                //将map对象存储在userList数组中
                userList.add(map);
            }
            //[{age=Avenstar4, name=Avenstar4}]
            map.put("elList", userList);
            //返回视图
            return "system/userList";
        }
        
        
        //方式二：ModelAndView
        @RequestMapping(value="test2", method=RequestMethod.GET)
        public ModelAndView list2(Model model){
            //创建一个视图对象
            ModelAndView view = new ModelAndView();
            //创建一个数组对象
            List<Map<String, Object>> userList = new ArrayList<Map<String, Object>>();
            for (int i = 0; i < 5; i++) {
                //存储对象map<K, V>
                Map<String, Object> map = new HashMap<String, Object>();
                map.put("name", "HelloKitty"+i);
                map.put("age", i);
                map.put("dept", "技术部"+i);
                userList.add(map);
            }
            //绑定数据
            model.addAttribute("userList", userList);
            //设置视图
            view.setViewName("system/userList");
    
            return view;
        }
        
        
        //方式三：AJAX
        //接收参数：@RequestParam(value="username", required=true, defaultValue="hello") String username
        @RequestMapping(value="/test3", method=RequestMethod.POST)
        @ResponseBody
        public Map<String, Object> list3(HttpServletRequest request, @RequestParam(value="username", required=true, defaultValue="hello") String username){
           
            Map<String, Object> map = new HashMap<>();
            //创建一个数组对象
            List<Map<String, Object>> userList = new ArrayList<Map<String, Object>>();
            for (int i = 0; i < 5; i++) {
                //存储对象map<K, V>
                Map<String, Object> map1 = new HashMap<String, Object>();
                map1.put("name", "HelloKitty"+i);
                map1.put("age", i);
                map1.put("dept", "技术部"+i);
                userList.add(map1);
            }
            
            map.put("userList", userList);
    
            return map;
        }
    
    }

[https_www.cnblogs.com_zjf-1992_p_5736101.html]: https://www.cnblogs.com/zjf-1992/p/5736101.html
[Link 1]: http://www.amazon.cn/gp/product/B001130JN8/ref=as_li_qf_sp_asin_il_tl?ie=UTF8&tag=importnew-23&linkCode=as2&camp=536&creative=3200&creativeASIN=B001130JN8
[format_png]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly9pbWFnZXMyMDE1LmNuYmxvZ3MuY29tL2Jsb2cvODE5MTY5LzIwMTYwOC84MTkxNjktMjAxNjA4MDQxMjM4MDI4NTYtNzg3NDA5NjAwLnBuZw?x-oss-process=image/format,png
[format_png 1]: http://www.importnew.com/15141.html
[format_png 2]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly9pbWFnZXMyMDE1LmNuYmxvZ3MuY29tL2Jsb2cvODE5MTY5LzIwMTYwOC84MTkxNjktMjAxNjA4MDUxNTMzMjUyNjItMTQ3OTQ2MTU0Ni5wbmc?x-oss-process=image/format,png
[format_png 3]: /images/20230531/9d817d2fb19745d49562b9a28eba713c.png