Spring boot mybatis 사용법

mybatis는 크게 2가지로 자바파일을 이용하는 방법과 xml을 이용하는 방법 두가지가 존재한다 

 

 

 

기본세팅

 

application.properties

#db연결 
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/bootex?serverTimezone=Asia/Seoul
spring.datasource.username=root
spring.datasource.password=12345

 

 

pom.xml

<dependency>
      <groupId>org.mybatis.spring.boot</groupId>
      <artifactId>mybatis-spring-boot-starter</artifactId>
      <version>2.1.2</version>
</dependency>
<dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <scope>runtime</scope>
</dependency>

 

 

자바 어노테이션을 이용하는 방법 

 

1. mapper 패키지를 만들고 mapperinterface를 만든다 

 

 

 

BootMapper

package com.example.demo.mapper;

import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;

import com.example.demo.dto.User;

public interface BootMapper {
	@Select("select * from user where age = #{age}")
	public User getUserAge(@Param("age") int age ) throws Exception;
	
}

 

 

 

 

2. DTO 클래스인 User class를 생성한다 

 

User

package com.example.demo.dto;

import lombok.Data;
import lombok.ToString;

@Data
//uid를 제외하여 출력
@ToString(exclude = {"uid"})
public class User {
	String name;
	String uid;
	int age;
	

}

 

 

 

3. Application.java 에 @MapperScan을 등록하여 mapper를 스캔할 수 있도록 한다 

 

package com.example.demo;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan(value= {"com.example.demo.mapper"})
public class BootexApplication {

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

}

 

 

4. JUnitTest를 하기 위해 @Autowired 를통해 BootMapper를 의존주입하여 mapperTest()를 실행한다.

 

package com.example.demo;

import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.Assert.assertTrue;
import static org.junit.jupiter.api.Assertions.assertEquals;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;

import javax.sql.DataSource;

import org.junit.Ignore;
import org.junit.jupiter.api.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import com.example.demo.dto.User;
import com.example.demo.mapper.BootMapper;

@RunWith(SpringRunner.class)
@SpringBootTest
class BootexApplicationTests {
	@Autowired
	private DataSource ds;

	@Autowired
	BootMapper mapper;
	
	@Test
	public void mapperTest() throws Exception{
		User user = mapper.getUserAge(1);
		System.out.println("User : "+user);
		assertEquals("장친수", user.getName());
		
		
	}
	
	
	@Ignore @Test
	public void testDataSource() throws Exception {
		System.out.println("DS=" + ds);
		try (Connection conn = ds.getConnection()) {
			System.out.println("Cooooooooonn=" + conn);
			assertThat(conn).isInstanceOf(Connection.class);
			assertEquals(100, getLong(conn, "select 100"));
		
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	
}

 

5. 결과 

 

정상적으로 exclude한 uid를 제외하고 값이 출력 되는 것을 확인할수있다.

 

 

 

 

 

XML을 이용하는 방법

 

 

1. mapper 패키지를 만들고 mapperinterface를 만든다 

 

 

 

 

BootMapper

package com.example.demo.mapper;

import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;

import com.example.demo.dto.User;

public interface BootMapper {
	public User getUserAge(@Param("age") int age ) throws Exception;
	
}

 

 

 

2. src/main/resources 밑에 mappers폴더를 만든다. 

 

 

3. mapper 밑에 bootMapper.xml을 만든다 

<?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">

<!-- 다른 mapper와 중복되지 않도록 네임스페이스 기재 -->
<mapper namespace="com.example.demo.mapper.BootMapper">
	<select id="getUserAge" resultType="com.example.demo.dto.User">
		select * from user where age = #{age}
	</select>
</mapper>

 

※  namespace 는 mapper클래스와 동인한 패키지명을 입력(bootMapper interface) , id 는 메소드명과 일치해야한다

 

 

 

 

4. application.properties에 mapper의 위치를 등록한다(안할 경우 Mapper.xml을 찾지 못해 에러발생) 

 

#mybatis
mybatis.mapper-locations=classpath:/mappers/*Mapper.xml

 

 

 

 

5. Application.java 에 @MapperScan을 등록하여 mapper를 스캔할 수 있도록 한다 

 

package com.example.demo;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
@MapperScan(value= {"com.example.demo.mapper"})
public class BootexApplication {

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

}

 

 

 

 

6. JUnitTest를 하기 위해 @Autowired 를통해 BootMapper를 의존주입하여 mapperTest()를 실행한다.

 

package com.example.demo;

import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.Assert.assertTrue;
import static org.junit.jupiter.api.Assertions.assertEquals;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.Statement;

import javax.sql.DataSource;

import org.junit.Ignore;
import org.junit.jupiter.api.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import com.example.demo.dto.User;
import com.example.demo.mapper.BootMapper;

@RunWith(SpringRunner.class)
@SpringBootTest
class BootexApplicationTests {
	@Autowired
	private DataSource ds;

	@Autowired
	BootMapper mapper;
	
	@Test
	public void mapperTest() throws Exception{
		User user = mapper.getUserAge(2);
		System.out.println("User : "+user);
		assertEquals("pooney", user.getName());
		
		
	}
	
	
	@Ignore @Test
	public void testDataSource() throws Exception {
		System.out.println("DS=" + ds);
		try (Connection conn = ds.getConnection()) {
			System.out.println("Cooooooooonn=" + conn);
			assertThat(conn).isInstanceOf(Connection.class);
			assertEquals(100, getLong(conn, "select 100"));
		
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	
}

 

 

 

 

7. 결과 

 

User name pooney, age 2가 정상적으로 출력되는 것을 확인 할 수 있다.