SpringBoot整合Mybatis

一、创建springboot项目

1.1、导入web、jdbc、mysql驱动依赖，以及如下依赖

<!-- 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>2.2.2</version>
        </dependency>

1.2、删除项目中不必要文件，得到一个简单的springboot项目

1.3、测试数据库表如下

二、测试

2.1、在application.properties配置如下

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

#整合mybatis
mybatis.type-aliases-package=com.massimo.pojo
mybatis.mapper-locations=classpath:mybatis/mapper/*.xml

2.2、编写数据库表对应的实体类

package com.massimo.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class User {

    private int id;
    private String name;
    private String password;
}

这里用lombok创建getter、setter、以及构造方法…

2.3、编写UserMapper

package com.massimo.mapper;

import com.massimo.pojo.User;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;

import java.util.List;

//这个注解表示这是一个mybatis的mapper
@Mapper
@Repository
public interface UserMapper {

    List<User> queryUserList();

    User queryUserById(int id);

    int addUser(User user);

    int updateUser(User user);

    int deleteUser(int id);
}

2.4、编写UserMapper对应的UserMapper.xml

<?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.massimo.mapper.UserMapper">

    <select id="queryUserList" resultType="User">
        select * from user
    </select>

    <select id="queryUserById" resultType="User">
        select * from user where id=#{id}
    </select>

    <insert id="addUser" parameterType="User">
        insert into user(id,name,password) values (#{id},#{name},#{password})
    </insert>

    <update id="updateUser" parameterType="User">
        update user set name=#{name},password=#{password} where id=#{id}
    </update>

    <delete id="deleteUser" parameterType="int">
        delete from user where id=#{id}
    </delete>
</mapper>

2.5、编写UserController

package com.massimo.controller;

import com.massimo.mapper.UserMapper;
import com.massimo.pojo.User;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
public class UserController {

    @Autowired
    private UserMapper userMapper;

    @GetMapping("/queryUserList")
    public List<User> queryUserList(){
        List<User> userList = userMapper.queryUserList();
        for (User user : userList) {
            System.out.println(user);
        }
        return userList;
    }

    @GetMapping("/queryUserById")
    public User queryUserById(int id){
        User user = userMapper.queryUserById(id);
        System.out.println(user);
        return user;
    }

    @GetMapping("/addUser")
    public String addUser(User user){
        int i = userMapper.addUser(new User(18, "李云龙", "213456"));
        return "添加成功！";
    }

    @GetMapping("/updateUser")
    public String updateUser(User user){
        int i = userMapper.updateUser(new User(1, "小李子", "987689"));
        return "更新成功！";
    }

    @GetMapping("/deleteUser")
    public String deleteUser(int id){
        int i = userMapper.deleteUser(id);
        return "删除成功！";
    }
}

三、项目结构