SpringBoot集成之Mybatis

素颜马尾好姑娘i 2021-10-15 22:01 475阅读 0赞

今天抽点时间做了一下关于springboot和mybatis整合相关知识，阅读本文章默认有springboot和mybatis的基础。

### 首先先创建一个springboot工程，导入相应的依赖 ###

<dependencies>
        <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    
        <dependency>
          <groupId>org.springframework.boot</groupId>
          <artifactId>spring-boot-starter-test</artifactId>
          <scope>test</scope>
        </dependency>
    
        <dependency>
          <groupId>mysql</groupId>
          <artifactId>mysql-connector-java</artifactId>
        </dependency>
    
        <dependency>
          <groupId>org.mybatis.spring.boot</groupId>
          <artifactId>mybatis-spring-boot-starter</artifactId>
          <version>1.3.0</version>
        </dependency>
      </dependencies>

### 创建实体类和数据库表 ###

package com.example.demo.entity;
    
    /**
     * Created by linjiaming
     */
    public class User {
        public Integer id;
        private String name;
        private Integer age;
    
        public Integer getId() {
            return id;
        }
    
        public void setId(Integer id) {
            this.id = id;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    
        public Integer getAge() {
            return age;
        }
    
        public void setAge(Integer age) {
            this.age = age;
        }
    }

![20190819175145154.png][]

### 分别创建Controller，Service和Dao ###

package com.example.demo.controller;
    
    import com.example.demo.entity.User;
    import com.example.demo.service.UserService;
    import com.fasterxml.jackson.annotation.JsonTypeInfo.Id;
    import javax.annotation.Resource;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestParam;
    import org.springframework.web.bind.annotation.RestController;
    
    /**
     * Created by linjiaming
     */
    @RestController
    public class UserController {
    
        @Resource
        UserService userService;
    
        @RequestMapping("user")
        public User hello(@RequestParam(value = "id") Integer id){
            User info = userService.getUserInfoById(id);
            return info;
        }
    }

package com.example.demo.service.impl;
    
    import com.example.demo.dao.UserDao;
    import com.example.demo.entity.User;
    import com.example.demo.service.UserService;
    import javax.annotation.Resource;
    import org.springframework.stereotype.Service;
    
    /**
     * Created by linjiaming
     */
    @Service("UserService")
    public class UserServiceImpl implements UserService {
    
        @Resource
        UserDao userDao;
    
        @Override
        public User getUserInfoById(Integer id) {
            User info = userDao.getUserInfoById(id);
            return info;
        }
    }

package com.example.demo.dao;
    
    import com.example.demo.entity.User;
    import org.springframework.stereotype.Repository;
    
    /**
     * Created by linjiaming
     */
    @Repository
    public interface UserDao {
    
        User getUserInfoById(Integer id);
    }

### Mapper文件信息 ###

<?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.demo.dao.UserDao" >
      
      <resultMap id="BaseResultMap" type="com.example.demo.entity.User" >
        <id column="id" property="id" jdbcType="INTEGER" />
        <result column="name" property="name" jdbcType="VARCHAR" />
        <result column="age" property="age" jdbcType="INTEGER" />
      </resultMap>
    
      <sql id="Base_Column_List" >
            id, name, age
        </sql>
    
      
      <select id="getUserInfoById" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
        select
        <include refid="Base_Column_List" />
        from t_user
        where id = #{id,jdbcType=INTEGER}
      </select>
    </mapper>

### 配置文件属性 ###

server.port=8080
    #mysql6以上版本使用com.mysql.cj.jdbc.Driver
    spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
    spring.datasource.url=jdbc:mysql://localhost:3306/fulan?useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC
    spring.datasource.username=root
    spring.datasource.password=123456
    #mapper文件位置
    mybatis.mapperLocations=classpath:mappers/*.xml

### 启动类上添加接口扫描注解 ###

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

### 启动后结果 ###

![20190819175748887.png][]

[20190819175145154.png]: /images/20211015/6862943b56fd4e998e0d8fb195c1d4e1.png
[20190819175748887.png]: /images/20211015/51ab8ce9bc4844f59c4d02a8b82cbc9f.png