一冯吓、導入相關依賴

<dependency>
   <groupId>org.mybatis.spring.boot</groupId>
   <artifactId>mybatis-spring-boot-starter</artifactId>
   <version>2.1.1</version>
</dependency>
<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>8.0.25</version>
</dependency>

二 配置數(shù)據(jù)源

spring.profiles.active=uat
spring.datasource.username=root
spring.datasource.password=12345678
#mysql8的驅動包
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/nacos?serverTimeZone=UTC&useUnicode=true&characterEncoding=utf8
#設置mapper.xml的位置 不然mybatis掃描不到mapper.xml的配置文件 會報無效的綁定錯誤
mybatis.mapper-locations=classpath:mapper/*.xml

三 配置實體類

@Data
public class ConfigInfo implements Serializable {

    private static final long serialVersionUID = 6337622087324151434L;

    private Long id;
    private String dataId;
    private String groupId;
    private String content;
    private String md5;
    private Date gmtCreate;
    private Date gmtModified;
    private String srcUser;
    private String srcIp;
    private String appName;
    private String tenantId;
    private String cDesc;
    private String cUse;
    private String effect;
    private String type;
    private String cSchema;
}

四 配置mapper.xml

<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.xxx.test.springboot2.mapper.ConfigInfoMapper">

    <resultMap type="com.xxx.test.springboot2.entity.ConfigInfo" id="configInfoMap">
        <id column="id" property="id" jdbcType="BIGINT" javaType="java.lang.Long"/> <!--jdbcType必須大寫 -->
        <result column="data_id" property="dataId" javaType="java.lang.String" jdbcType="VARCHAR"/>
        <result column="group_id" property="groupId"/> <!--省略javaType與jdbcType mybatis會自動進行映射 -->
        <result column="content" property="content"/>
        <result column="md5" property="md5"/>
        <result column="gmt_create" property="gmtCreate"/>
        <result column="gmt_modified" property="gmtModified"/>
        <result column="src_user" property="srcUser"/>
        <result column="src_ip" property="srcIp"/>
        <result column="app_name" property="appName"/>
        <result column="tenant_id" property="tenantId"/>
        <result column="c_desc" property="cDesc"/>
        <result column="c_use" property="cUse"/>
        <result column="effect" property="effect"/>
        <result column="type" property="type"/>
        <result column="c_schema" property="cSchema"/>
    </resultMap>

    <select id="queryAll" resultMap="configInfoMap">
        select * from config_info;
    </select>
</mapper>

五 配置mapper類

//mapper類是一個接口
@Mapper
public interface ConfigInfoMapper {

    List<ConfigInfo> queryAll();
}

六 配置啟動類

//因為在mapper接口上加了@Mapper注解 所以不需要再在啟動類上添加@MapperScan注解了
@SpringBootApplication
public class App {

    public static void main(String[] args) {
        SpringApplication.run(App.class, args);
    }
}