本文共 7171 字，大约阅读时间需要 23 分钟。

【开发篇】10分钟快速上手spring boot+mybatis增删改查

首先来，温故而知新！！！

之前的预备知识：

复习完之前，那么接接下来乘风破浪吧！！！

本次用IDEA带领你快速上手spring boot+mybatis进行用户的增删改查操作。

一、新建spring boot 项目

本次所用的依赖包含spring boot的核心web以及mysql,mybatis依赖包。

其依赖在pom.xml中如下所示:

   
       
    
     org.mybatis.spring.boot
        
    
     mybatis-spring-boot-starter
        
    
     2.1.3
    
   
   
       
    
     mysql
        
    
     mysql-connector-java
    
   

二、项目中配置mysql和mybatis

本次通过application.yml文件来配置信息，将application.properties文件删除，重新新建一个application.yml文件。其内容如下：

spring:  profiles:    active: dev

之后新建一个application-dev.yml文件，包含项目启动的端口，数据库的连接参数，以及mybatis的配置。

其内容如下：

# 1.项目启动的端口server:  port: 8080# 2.数据库连接参数spring:  datasource:    driver-class-name: com.mysql.cj.jdbc.Driver    url:  jdbc:mysql://127.0.0.1:3306/user?serverTimezone=UTC&useSSL=false    username: root    password: 123# 3.Mybatis的配置mybatis:  # mybatis配置文件所在位置  config-location: classpath:mybatis-config.xml  # mapper配置文件所在位置  mapper-locations: classpath:mapper/*.xml  # 实体类所在的位置  type-aliases-package: com.example.area_mybatis.entity

三、Mybatis配置文件

在resources下新建mybatis-config.xml文件，其主要内容如下

四、代码部分编写

代码包含了

• entity: 实体类的编写
• mapper:数据处理层
• service：业务逻辑层
• controller：控制器

1.entity/User

package com.example.area_mybatis.entity;/** * @author : codingchao * @date : 2020-08-15 12:04 * @Description: **/public class User {    private  int id;    private String name;    private String password;    private String number;    public User(String name, String password, String number) {        this.name = name;        this.password = password;        this.number = number;    }    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;    }    public String getNumber() {        return number;    }    public void setNumber(String number) {        this.number = number;    }}

2.mapper/UserMapper

package com.example.area_mybatis.mapper;import com.example.area_mybatis.entity.User;import org.apache.ibatis.annotations.Mapper;import org.springframework.stereotype.Repository;import java.util.List;/** * @author : codingchao * @date : 2020-08-15 12:05 * @Description: **/@Repository@Mapperpublic interface UserMapper {    // 通过name查询    List
   
     findUserByName(String name);    // 通过id查询    User findUserById(Integer id);    // 列出全部的user信息    public List
    
      ListUser();    // 插入user信息    public  int insertUser(User user);    // 删除user信息    public int delete(int id);    // 更新user信息    public int Update(User user);}
    
   

3.service/UserService

package com.example.area_mybatis.service;import com.example.area_mybatis.entity.User;import java.util.List;public interface UserService {    public List
   
     findByName(String name);    public User findById(Integer id);    public List
    
      ListUser();    public User insertUser(String name, String number,String password);    public int delete(Integer id);    public int Update(Integer id,String number);}
    
   

4.service/impl/UserServiceImpl

package com.example.area_mybatis.service.impl;import com.example.area_mybatis.entity.User;import com.example.area_mybatis.mapper.UserMapper;import com.example.area_mybatis.service.UserService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import java.util.List;/** * @author : codingchao * @date : 2020-08-15 12:05 * @Description: **/@Servicepublic class UserServiceImpl implements UserService {    @Autowired    private UserMapper userMapper;    public List
   
     findByName(String name){        return userMapper.findUserByName(name);    }    public User findById(Integer id){        return userMapper.findUserById(id);    }    public List
    
      ListUser(){        return userMapper.ListUser();    }    public User insertUser(String name, String number,String password){        User user = new User(name,number,password);        userMapper.insertUser(user);        return user;    }    public int delete(Integer id){        return userMapper.delete(id);    }    public int Update(Integer id,String number){        User user = userMapper.findUserById(id);        user.setNumber(number);        return userMapper.Update(user);    }}
    
   

5.在controller/CRUD

package com.example.area_mybatis.controller;import com.example.area_mybatis.entity.User;import com.example.area_mybatis.service.impl.UserServiceImpl;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.*;import java.util.List;/** * @author : codingchao * @date : 2020-08-15 12:05 * @Description: **/@RestController@RequestMapping(value="/crud",method = {RequestMethod.GET,RequestMethod.POST})public class CRUD {    @Autowired    private UserServiceImpl userService;    @GetMapping("/listUser")    public List
   
     ListUser(){        return userService.ListUser();    }    @PostMapping(value="listUserByName")    public List
    
      ListUserByNAME(@RequestParam("name") String name){        return userService.findByName(name);    }    @PostMapping(value="delete")    public String delete(@RequestParam("id") Integer id){        int result = userService.delete(id);        if (result >= 1){            return "删除成功";        }else{            return "删除失败";        }    }    @PostMapping(value = "insert")    public User insert(@RequestParam("name")String name,                       @RequestParam("number")String number,                       @RequestParam("password")String password){        return userService.insertUser(name,number,password);    }    @PostMapping(value = "update")    public String update(@RequestParam("id") Integer id,                       @RequestParam("number")String number){        int result = userService.Update(id,number);        if (result >= 1){            return "修改成功";        }else{            return "修改失败";        }    }}
    
   

五、数据库设计以及UserMapper数据库语句编写

数据库设计如下表所示

之后在resource下新建mapper文件夹，在其下新建UserMapper.xml文件

   
       
            
             
             
         
        
            SELECT * FROM user        
            SELECT * FROM user where name=#{name}        
            SELECT  * FROM user where  id=#{id}        
    
             INSERT INTO user(            name,password,number        )        VALUES(        #{name},#{password},#{number}        )    
        
    
             update user        
                 
      
       name=#{name},
                  
      
       password=#{password},
                  
      
       number=#{number}
              
             where id=#{id}    
        
    
             delete from user where id=#{id}    
    
   

六、postman测试

1.测试查询全部信息

http://localhost:8080/crud/listUser

2.通过名字来查询用户

http://localhost:8080/crud/listUserByName?name=A

3.新增用户

http://localhost:8080/crud/insert?name=B&number=202002&password=123456

4.删除用户

http://localhost:8080/crud/delete?id=3

那么，这期就结束了！！！

继续学习去！！！

转载地址：http://megbf.baihongyu.com/