1. 5個包 放到 POM 

<!--mybatis -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
</dependency>
<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
 
    <version>1.1.1</version>
</dependency>
<!--commons -->
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.6</version>
</dependency>
<dependency>
    <groupId>
 
commons-configuration</groupId>
    <artifactId>commons-configuration</artifactId>
    <version>1.10</version>
</dependency>
<dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
    <version>2.5</version>
 
</dependency>

2. 生產專案MAVEN 依賴


3. config  aplication.java
//增加持久層
@MapperScan("com.jm.dao")


4. config application.yml




datasource:
        url: jdbc:oracle:thin:@20.1.10.18:1521:jiumao
        username: jiumao
        password: 123456


    mybatis:
        configuration:
            map-underscore-to-camel-case: true




5.dao 


import com.jm.Model.UserDB;
import org.apache.ibatis.annotations.Select;


//注意這裡是interface
public interface UserMapper {
   //@Select("select `username`, `password` from user where username = #{username}")
   // User getByUsername(String username);
    //z這裡沒有分號
    @Select("select 'userid' , 'username' , 'userno' ,'password'from users where username=#{username}")
    UserDB getByUsername(String username);




}


6.  @Autowired controller
@Autowired
    UserMapper userMapper;