RESTful风格

（一）什么是RESTful

（1）RESTful不是一套标准，只是一套开发方式，构架思想

（2）url更加简洁

（3）有利于不同系统之间的资源共享

（二）概述

RESTful具体来讲就是HTTP协议的四种形式，四种基本操作

GET:获取资源

POST：新建资源

PUT：修改资源

DELETE：删除资源

（三）实例

（1）功能

1.数据的增删改查

2.controller层的应用

3.HTTP四种基本操作的应用

（2）代码实现

1.pom.xml


       
          
       
        junit
           
       
        junit
           
       
        4.11
         
        
          
       
        org.springframework
           
       
        spring-webmvc
           
       
        5.1.3.RELEASE
         
        
          
       
        javax.servlet
           
       
        jstl
           
       
        1.2

2.web.xml


       
      
       Archetype Created Web Application
        
          
       
        SpringMVC
           
       
        org.springframework.web.servlet.DispatcherServlet
           
             
        
         contextConfigLocation
              
        
         classpath:springmvc.xml
            
         
        
          
       
        SpringMVC
           
       
        /
         
        
        
          
       
        hiddenHttpMethodFilter
           
       
        org.springframework.web.filter.HiddenHttpMethodFilter
         
        
          
       
        hiddenHttpMethodFilter
           
       
        /*

3.springmvc.xml

4.User.java

package entiry;public class User {    private int id;    private String name;    private String password;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }    @Override    public String toString() {        return "User{" +                "id=" + id +                ", name='" + name + '\'' +                ", password='" + password + '\'' +                '}';    }}

5.UserDao.java

package dao;import entiry.User;import org.springframework.stereotype.Repository;import java.util.Collection;import java.util.HashMap;import java.util.Map;@Repositorypublic class UserDao {    private Map
     
       map=new HashMap
      
       ();    /**     * 增加     * @param user     */    public void add(User user){        map.put(user.getId(),user);    }    /**     * 查询所有     * @return     */    public Collection
       
         selectAll(){        return map.values();    }    /**     * 通过id查询     * @param id     * @return     */    public User select(int id){        return map.get(id);    }    /**     * 修改     * @param user     */    public void update(User user){        map.put(user.getId(),user);    }    /**     * 删除     * @param id     */    public void delete(int id){        map.remove(id);    }}

6.UserController.java

package controller;import dao.UserDao;import entiry.User;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.*;import org.springframework.web.servlet.ModelAndView;@Controllerpublic class UserController {    @Autowired    private UserDao userDao;    @PostMapping("/add")    public String add(User user){       userDao.add(user);       //重定向到selectAll       return "redirect:/selectAll";    }    @GetMapping("/selectAll")    public ModelAndView selectAll(){        ModelAndView modelAndView=new ModelAndView();        modelAndView.addObject("users",userDao.selectAll());        modelAndView.setViewName("select");        for(User user:userDao.selectAll()){            System.out.println(user);        }        return modelAndView;    }    @GetMapping("/select/{id}")    public ModelAndView select(@PathVariable(value="id") int id){        ModelAndView modelAndView=new ModelAndView();        modelAndView.setViewName("update");        modelAndView.addObject("user",userDao.select(id));        return modelAndView;    }    @PutMapping("/update")    public String update(User user){        userDao.update(user);        return "redirect:/selectAll";    }    @DeleteMapping("/delete/{id}")    public String delete(@PathVariable(value="id")int id){        userDao.delete(id);        return "redirect:/selectAll";    }}

7.add.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>    Title
     
          id:
      
      
    用户名：
      
      
    密码：

8.select.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %><%@page isELIgnored="false" %><%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>    Title
             
     
     
                                 id                 用户名                 密码                                            
                               ${user.id}                     ${user.name}                     ${user.password}

9.update.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>    Title
     
      
                                    id                              
                             用户名                              
                             密码