Spring Boot - Mybatis 연동

Spring Boot - Mybatis 연동

• Dependency 설정

  pom.xml

    <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
        <version>2.1.4</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-jdbc</artifactId>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.mariadb.jdbc</groupId>
        <artifactId>mariadb-java-client</artifactId>
        <scope>runtime</scope>
    </dependency>
  

• Hikari Datasource 환경 설정

  application.yml

    spring:
    datasource:
        hikari:
        driver-class-name: com.mysql.cj.jdbc.Driver
        jdbc-url: jdbc:mysql://localhost:3306/testdb?useSSL=false&useUnicode=true&characterEncoding=utf8&serverTimezone=UTC
        username: root
        password: 1234
        maximum-pool-size: 50
        max-lifetime: 30000
        idle-timeout: 28000
        connection-timeout: 0
        transaction-isolation: TRANSACTION_READ_UNCOMMITTED
  

• DataSuorce 설정

  MariaDataSourceConfiguration.java

    @Configuration
    public class MariaDataSourceConfiguration {
  
        @Bean
        @Qualifier("hikariConfig")
        @ConfigurationProperties(prefix="spring.datasource.hikari")
        public HikariConfig hikariConfig() {
            return new HikariConfig();
        }
  
        @Bean
        @Primary
        @Qualifier("dataSource")
        public DataSource dataSource() throws Exception {
            return new HikariDataSource(hikariConfig());
        }
    }
  

• MyBatis 설정

  MyBatisConfiguration.java

    @Configuration
    public class MyBatisConfiguration {
        @Primary
        @Bean(name = "sqlSessionFactory")
        public SqlSessionFactory sqlSessionFactory(
                @Qualifier("dataSource") DataSource dataSource, ApplicationContext applicationContext) throws Exception {
            SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
            sqlSessionFactoryBean.setDataSource(dataSource);
            sqlSessionFactoryBean.setConfigLocation(applicationContext.getResource("classpath:mybatis/mybatis-config.xml"));
            sqlSessionFactoryBean.setMapperLocations(applicationContext.getResources("classpath:mybatis/**/*.xml"));
            return sqlSessionFactoryBean.getObject();
        }
  
        @Primary
        @Bean(name = "sqlSessionTemplate")
        public SqlSessionTemplate sqlSessionTemplate(
                @Qualifier("sqlSessionFactory") SqlSessionFactory sqlSessionFactory) {
            return new SqlSessionTemplate(sqlSessionFactory);
        }
    }
  

  mybatis-config.xml

    <?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
  
    <configuration>
  
        <settings>
            <setting name="mapUnderscoreToCamelCase" value="true"/>
        </settings>
  
        <typeAliases>
            <typeAlias alias="userDto" type="com.example.dto.UserDto"/>
        </typeAliases>
  
        <typeHandlers>
        </typeHandlers>
  
    </configuration>
  

  ##### 공식 문서를 보면 datasource를 감지해서 SqlSessionFactory을 만들고, 만들어진 SqlSessionFactory로 SqlSessionTemplate을 자동으로 만든다고 한다. 따라서 특별한 설정이 필요하지 않을 경우 위의 MyBatisConfiguration.class는 없어도 문제가 없다.

• DTO 생성

  UserDto.class

    @Data
    public class UserDto {
        String id;
        String password;
        String name;
        String email;
    }
  

• 세 가지 사용 방법

  • Mapper 사용

    UserMapper.class

      @Mapper
      public interface UserMapper {
          @Select("SELECT * FROM user WHERE id = #{id}")
          UserDto findById(@Param("id") String id);
      }
    

  • SqlSessionFactory 사용

    UserDaoMapper.class

      @Mapper
      public interface UserDaoMapper {
          UserDto selectUserById(String id);
      }
    

    user-dao-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.example.dao.UserDaoMapper">
          <select id="selectUserById" parameterType="String" resultType="UserDto">
              SELECT *
              FROM USER
              WHERE id = #{value}
          </select>
      </mapper>
    

  • SqlSessionTemplate 사용

    UserDao.class

      @Component
      public class UserDao {
          private final SqlSession sqlSession;
    
          public UserDao(@Qualifier("sqlSessionTemplate") SqlSession sqlSession) {
              this.sqlSession = sqlSession;
          }
    
          public UserDto selectUserById(String id){
              return this.sqlSession.selectOne("com.example.dao.UserDao.selectUserById", id);
          }
      }
    

    user-dao.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.example.dao.UserDao">
          <select id="selectUserById" parameterType="String" resultType="UserDto">
              SELECT *
              FROM USER
              WHERE id = #{value}
          </select>
      </mapper>
    

• 실행 및 결과

  TestMyBatis.class

    @SpringBootApplication
    @Slf4j
    public class TestMyBatisApplication implements CommandLineRunner {
  
        private final UserMapper userMapper;
        private final UserDao userDao;
  
        public TestMyBatisApplication(UserMapper userMapper, UserDao userDao) {
            this.userMapper = userMapper;
            this.userDao = userDao;
        }
  
        @Autowired
        private UserDaoMapper userDaoMapper;
  
        public static void main(String[] args) {
            SpringApplication.run(TestMyBatisApplication.class, args);
  
        }
  
        @Override
        public void run(String... args) throws Exception {
            log.info("result -> {}",this.userMapper.findById("abc"));
            log.info("result -> {}",this.userDao.selectUserById("abc"));
            log.info("result -> {}",this.userDaoMapper.selectUserById("abc"));
        }
    }
  

  result log

   	result -> UserDto(id=abc, password=qwer, name=1234, email=zxcv)
    result -> UserDto(id=abc, password=qwer, name=1234, email=zxcv)
   	result -> UserDto(id=abc, password=qwer, name=1234, email=zxcv)
  

  Introduction What is MyBatis-Spring-Boot-Starter?

  MyBatis @Mapper 인터페이스는 어떻게 스프링 빈으로 와이어될 수 있을까?