[Java] 마이바티스(Mybatis) 란? 그리고 사용방법

Mybatis 사이트

 

Ibatis의 다음버젼 Mybatis

- java Persistence framework의 일종이다.

- 데이터의 저장, 조회, 변경, 삭제를 다루는 클래스 및 설정 파일의 집합

- 퍼시스턴스 프레임 워크를 사용하면 간단하게 DB와 연동된다.

 

TransactionManager 타입

JDBC(JDBC커밋과 롤백을 처리하기 위해 사용) , MANAGED(컨테이너가 관리)

 

DatasourceSource 타입

- UNPOOLED : 매번 커넥션을 열고 닫는다.

- POOLED : 커넥션 풀이 적용

 

pom.xml 추가

<dependencies>
		<!-- Mybatis연동 -->
		<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
		<dependency>
			<groupId>org.mybatis</groupId>
			<artifactId>mybatis</artifactId>
			<version>3.5.2</version>
		</dependency>

		<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
		<dependency>
			<groupId>mysql</groupId>
			<artifactId>mysql-connector-java</artifactId>
			<version>8.0.17</version>
		</dependency>

	</dependencies>

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>
	
	<!-- typeAliases는 무조건 환경설정보다 상위에 위치해야 한다. -->
	<typeAliases>
		<typeAlias type="t_tok03.Student" alias="StudentType"/>
	</typeAliases>
	
	<environments default="development">
		<environment id="development">
			<transactionManager type="JDBC"/>
			<dataSource type="POOLED">
				<property name="driver" value="com.mysql.cj.jdbc.Driver"/>
				<property name="url" value="jdbc:mysql://localhost:3306/test?serverTimezone=UTC"/>
				<property name="username" value="root"/>
				<property name="password" value="0000"/>
			</dataSource>
		</environment>
	</environments>
	
	<mappers>
		<mapper resource="t_tok03/Student.xml"/>
	</mappers>
</configuration> 

Student.xml (mapper)

<?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 -->
<mapper namespace="Student">
	<select id="findAllStudent" resultType="StudentType">
		SELECT * FROM student
	</select>
</mapper>
  

Main.java

package t_tok03;

import java.io.IOException;
import java.io.Reader;
import java.util.List;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class Main {

	public static void main(String[] args) throws IOException {
		select(); 
	}

	public static void select() throws IOException {
		Reader reader = Resources.getResourceAsReader("t_tok03/mybatis-config.xml");
		SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
		SqlSession session = sqlSessionFactory.openSession();

		List<Student> list = session.selectList("Student.findAllStudent");
		System.out.println(list.size());

		for (Student s : list) {
			System.out.println(s);
		}
	}

}