springboot集成mybatis

1、添加依赖

        <!-- mysql -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>${mysql.version}</version>
        </dependency>
        <!-- mybatis -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>${mybatis-boot.version}</version>
        </dependency>

刷新maven，加载依赖

2、在application.properties中添加mybatis配置

spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.username=gpcj_2020
spring.datasource.password=111
spring.datasource.url=jdbc:mysql://192.168.1.101:3306/xxxx?allowMultiQueries=true

3、以上配置工作已经完成，然后开始创建实体类实现业务流程

创建包controller、entity、mapper、service。resources下创建mapping文件夹，用于写sql语句，也可以用注解的方式直接写在mapper文件里。下面直接贴代码

数据库表结构（之前小项目的表，直接拿来用）

CREATE TABLE `user` (
  `id` int(32) NOT NULL AUTO_INCREMENT,
  `userName` varchar(32) NOT NULL,
  `passWord` varchar(50) NOT NULL,
  `realName` varchar(32) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=utf8;

实体类User

package com.example.entity;
 
public class User {
    private Integer id;
    private String userName;
    private String passWord;
    private String realName;
 
    public Integer getId() {
        return id;
    }
 
    public void setId(Integer id) {
        this.id = id;
    }
 
    public String getUserName() {
        return userName;
    }
 
    public void setUserName(String userName) {
        this.userName = userName;
    }
 
    public String getPassWord() {
        return passWord;
    }
 
    public void setPassWord(String passWord) {
        this.passWord = passWord;
    }
 
    public String getRealName() {
        return realName;
    }
 
    public void setRealName(String realName) {
        this.realName = realName;
    }
}

控制器UserController

package com.example.controller;
 
import com.example.entity.User;
import com.example.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
 
/**
 * @Author:wjup
 * @Date: 2018/9/26 0026
 * @Time: 14:42
 */
 
@RestController
@RequestMapping("/testBoot")
public class UserController {
 
    @Autowired
    private UserService userService;
 
    @RequestMapping("getUser/{id}")
    public String GetUser(@PathVariable int id){
        return userService.Sel(id).toString();
    }
}

服务类UserService

package com.example.service;
 
import com.example.entity.User;
import com.example.mapper.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
 
@Service
public class UserService {
    @Autowired
    UserMapper userMapper;
    public User Sel(int id){
        return userMapper.Sel(id);
    }
}

mapper类UserMapper

package com.example.mapper;
 
import com.example.entity.User;
import org.apache.ibatis.annotations.Select;
import org.springframework.stereotype.Repository;
 
@Repository
public interface UserMapper {
 
    User Sel(int id);
}

UserMapping.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.example.mapper.UserMapper">
 
    <resultMap id="BaseResultMap" type="com.example.entity.User">
        <result column="id" jdbcType="INTEGER" property="id" />
        <result column="userName" jdbcType="VARCHAR" property="userName" />
        <result column="passWord" jdbcType="VARCHAR" property="passWord" />
        <result column="realName" jdbcType="VARCHAR" property="realName" />
    </resultMap>
 
    <select id="Sel" resultType="com.example.entity.User">
        select * from user where id = #{id}
    </select>
 
</mapper>

最终文件结构

image.png

4、完成以上，下面在启动类里加上注解用于给出需要扫描的mapper文件路径@MapperScan("com.example.mapper")

package com.example;
 
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
 
@MapperScan("com.example.mapper") //扫描的mapper
@SpringBootApplication
public class DemoApplication {
 
    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }
}

测试成功，就这样基本框架就搭建成功了
最后启动，浏览器输入地址看看吧：http://localhost:8080/testBoot/getUser/1