SpringBoot整合Mybatis

SpringBoot整合Mybatis

导入mybatis依赖

<!-- https://mvnrepository.com/artifact/org.mybatis.spring.boot/mybatis-spring-boot-starter -->
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>2.1.1</version>
</dependency>
​

整合测试（yaml方式）

1. 配置数据库

   spring:
     datasource:
       username: root
       password: 123456
       url: jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8
       driver-class-name: com.mysql.cj.jdbc.Driver

2. 在配置文件中整合mybatis

   #整合Mybatis
   mybatis:
     type-aliases-package: com.Gao.POJO #别名映射
     mapper-locations: classpath:mybatis/*.xml #.xml文件位置
     #此处若有问题，没有找到.xml则会报错
     #.BindingException: Invalid bound statement (not found): 

    

3. 创建一个实体类POJO(导入lombok来偷懒)

   package com.Gao.POJO;
   ​
   import lombok.AllArgsConstructor;
   import lombok.Data;
   import lombok.NoArgsConstructor;
   ​
   @Data
   @AllArgsConstructor
   @NoArgsConstructor
   public class SysUser {
   ​
     private int id;
     private String username;
     private String email;
     private String password;
     private String phoneNum;
   ​
   ​
   }

4. 创建Dao层的Mapper

   @Mapper//这个注解就是告诉spring，这是一个mybatis的mapper类， 到Dao层
   @Repository  //Dao层注册到spring容器中
   public interface UserMapper {
       List<SysUser> queryUserList();
   ​
       SysUser queryUserById(int id);
   ​
       int addUser(SysUser user);
   ​
       int updateUser(SysUser user);
   ​
       int deleteUser(int id);
   }

5. 在resources目录下创建mybatis包，创建对应的mapper的映射文件

   <?xml version="1.0" encoding="UTF-8" ?>
   <!DOCTYPE mapper
     PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
     "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
   <mapper namespace="com.Gao.Mapper.UserMapper">
   ​
   <select id="queryUserList" resultType="SysUser">
   select * from sys_user;
   </select>
   ​
   <select id="queryUserById" resultType="SysUser">
   select * from system_user where id = #{id};
   </select>
   ​
   <insert id="addUser" parameterType="SysUser" >
   insert into sys_user(username,email,password,phoneNum) values (#{username},#{email},#{password},#{phoneNum});
   </insert>
   ​
   <update id="updateUser" parameterType="SysUser">
   update sys_user set username = #{username}, email = #{email}, password = #{password}, phoneNum = #{phoneNum} where id = #{id};
   </update>
   ​
   <delete id="deleteUser" parameterType="int">
   delete from sys_user where id = #{id};
   </delete>
   </mapper>

6. 创建一个controller来进行测试

   @RestController
   public class MybatisController {
   ​
       @Autowired
       private UserMapper userMapper;
   ​
       @GetMapping("/userList")
       public List<SysUser> queryUserList(){
           List<SysUser> userList = userMapper.queryUserList();
           for (SysUser user : userList) {
               System.out.println(user);
           }
           return userList;
       }
   }

   测试结果完成~~

7.