SpringBoot整合mybatis的两种方法

1.全注解方式

1.1添加依赖

在pom.xml中添加如下依赖：

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.2.0</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

1.2配置数据源

在application.yml中添加数据源啊：

spring:
  datasource:
    url: jdbc:mysql://127.0.0.1:3306/samp_db?useUnicode=true&characterEncoding=utf8
    username: root
    password: root
    driver-class-name: com.mysql.jdbc.Driver

1.3添加实体类

package com.dylan.springdemo.entity;

/**
 * Created with IDEA
 * User: wangcheng
 * Date:2019/6/26
 * Time:下午3:34
 */
public class Student {
    /**
     * 姓名
     */
    private String name;
    /**
     * 学号
     */
    private String id;
    /**
     * 分数
     */
    private String score;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getId() {
        return id;
    }
    public void setId(String age) {
        this.id = id;
    }
    public String getScore() {
        return score;
    }
    public void setScore(String score) {
        this.score = score;
    }
}

1.4创建映射类

使用mapper注解

/**
 * Created with IDEA
 * User: wangcheng
 * Date:2019/6/26
 * Time:下午3:37
 */

@Mapper
public interface UserInfo {
    @Select("select * from t_usr_pinf where id='2' ")
    Student query();

}

1.5使用

@Autowired
    private UserInfo userInfo;
    @RequestMapping("/ParkingSet")
    private ParkingSetRspBO getParkingSet(@RequestBody ParkingSetReqBO parkingSetReqBO)  {
        Student student=userInfo.query();
        System.out.println(student.getName());
        }

2使用DAO+mapper

2.1 添加依赖

#指定mybatis映射文件的地址
mybatis:
  mapper-locations: classpath:mapper/*.xml

2.2 dao

package com.dylan.springdemo.dao;


import com.dylan.springdemo.entity.Student;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

/**
 * Created with IDEA
 * User: wangcheng
 * Date:2019/6/26
 * Time:下午3:37
 */

@Mapper
public interface UserInfo1 {
    Student query();

}

2.3 mapper

在resource下创建mapper目录，创建mapper(与DAO同名)：

<?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.dylan.springdemo.dao.UserInfo1"><select id="query" resultType="com.dylan.springdemo.entity.Student"  >
            select * from t_usr_pinf where id='2'
        </select>
</mapper>

3. 使用@MapperScan

相比于@mapper需要在每个mapper类添加注解，使用@MapperScan可以指定要扫描的mapper类所在包路径：

package com.dylan.springdemo;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;

@SpringBootApplication
@MapperScan(basePackages="com.dylan.springdemo.dao")
public class SpringdemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringdemoApplication.class, args);
    }
    @Bean
    RestTemplate restTemplate(){
        return new RestTemplate();
    }

}