springboot 集成mybatis

1、导入jar包

<!--mybatis连接mysql-->
  <dependency>
      <groupId>org.mybatis.spring.boot</groupId>
      <artifactId>mybatis-spring-boot-starter</artifactId>
      <version>1.3.2</version>
  </dependency>
 
  <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
  </dependency>
 
  <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.4.0</version>
  </dependency>

　2、在application.yml配置数据源（此处是mysql）和 mybatis

#连接数据库
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/demo?useUnicode=true&characterEncoding=utf8&zeroDateTimeBehavior=convertToNull&serverTimezone=UTC
    hikari:
      username: root
      password: 123456
 
 
mybatis:
  #配置mapper映射文件 classpath代表resources下
  mapper-locations: classpath:mapper/*.xml
  #打开sql执行日志
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl
    #所有pojo类所在包路径
  type-aliases-package: com.wwc.demo.pojo

3、创建实体类对象

public class UserInfo {
 
    private int id;
 
    private String userName;
 
    private String userPwd;
 
    public int getId() {
        return id;
    }
 
    public void setId(int id) {
        this.id = id;
    }
 
    public String getUserName() {
        return userName;
    }
 
    public void setUserName(String userName) {
        this.userName = userName;
    }
 
    public String getUserPwd() {
        return userPwd;
    }
 
    public void setUserPwd(String userPwd) {
        this.userPwd = userPwd;
    }
 
    public UserInfo(int id, String userName, String userPwd) {
        this.id = id;
        this.userName = userName;
        this.userPwd = userPwd;
    }
 
    public UserInfo() {
    }
 
    @Override
    public String toString() {
        return "UserInfo{" +
                "id=" + id +
                ", userName='" + userName + '\'' +
                ", userPwd='" + userPwd + '\'' +
                '}';
    }
}

　4、创建dao层使用注解@Mapper

@Mapper
public interface UserInfoDao {
 
    List<UserInfo> getList();
}

5、创建mybatis映射文件mapper.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.wwc.demo.dao.UserInfoDao">
　　<!-- 结果集与实体类映射-->
    <resultMap id="userInfoMap" type="com.wwc.demo.pojo.UserInfo">
        <id property="id" column="id" javaType="int" jdbcType="INTEGER"></id>
        <result property="userName" column="user_name" javaType="String" jdbcType="VARCHAR"></result>
        <result property="userPwd" column="user_pwd" javaType="String" jdbcType="VARCHAR"></result>
    </resultMap>
 
    <select id="getList" resultMap="userInfoMap">
        select * from user_info
    </select>
</mapper>