Java - Mybatis ( 일반 DML 호출 )

필요 lib : mybatis.jar   ,   ojdbc6 , 톰캣

# 개요 

      Java로 Mybatis사용시 데이터를 가져오는 방식은 to방식과 Map방식이 있다.

      이 두가지 방법을 구현해 보겠다.

    

1. to방식

to방식은 새로 하나 추가되서 두가지가 있는데 xml이용과 인터페이스이용법이다.

1) xml이용시

        parameter로 사용될시 대소문자구분( 이유는 #{seq} 와 #{SEQ}는 다름 )

        result로 사용시 대소문자 구분안함

2) 인터페이스이용시

        매퍼.xml이 사라지고 인터페이스에서 어노테이션에 쿼리를 주는방식

        

2. Map방식 ( hashmap )

Test.java    --    메인메서드

import java.io.*;

import java.util.HashMap;

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 Test {

public static void main(String[] args) {

       SqlSession session = null;

       

       try {

              String resource = "mybatis-config.xml";

              InputStream inputStream = Resources.getResourceAsStream(resource);

              SqlSessionFactory sqlSessionFactory = 

                            new  SqlSessionFactoryBuilder().build(inputStream);

              

              session = sqlSessionFactory.openSession();

       

              // HashMap방식

              HashMap<String, Object> toMap = new HashMap<String, Object>();

              toMap.put("SEQ", 1);

              

              

              HashMap<String, Object> fromMap 

                        =  session.selectOne("BoardMapper.selectBoardToMap", toMap);

              System.out.println( fromMap.get("SEQ") );

              System.out.println( fromMap.get("TITLE") );

              System.out.println( fromMap.get("CONTENT") );

              System.out.println( fromMap.get("HIT_CNT") );

              

              

              // TO방식

              Board board = new Board();

              board.setSeq(1);

              

              Board resutBoard 

                =  (Board)session.selectOne("BoardMapper.selectBoardToBean", board);

              

              System.out.println( resutBoard.getSeq() );

              System.out.println( resutBoard.getTitle() );

              System.out.println( resutBoard.getContent() );

              System.out.println( resutBoard.getHitCnt() );

              

              

              // TO방식 신규( BoardMapper.xml대신 BoardMapper인터페이스에 어노테이션사용 )

              // 장 : 리턴타입에 대해 형변환 필요없음

              //            , 문자열에 의존하지않음???

              // 단 : 오히려 쿼리복잡해지면 불편할듯?

              BoardMapper mapper = session.getMapper(BoardMapper.class);

              Board bo = mapper.selectBoard(1);

              

              System.out.println( bo.getSeq() );

              System.out.println( bo.getTitle() );

              System.out.println( bo.getContent() );

              System.out.println( bo.getHitCnt() );

              

       } catch (Exception e) {

              System.out.println(e.getMessage());

       }finally {

              session.close();

       }

       System.out.println("종료");

}

}

mybatis-config.xml   --마이바티스설정파일

    (원래 프로퍼티스로 password등을 주는데 어떻게 하는지 몰겟다.걍 바로줘버림)

<?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>

       <typeAliases>

              <typeAlias  alias="Board" type="Board"/>

       </typeAliases>

       <environments default="development">

              <environment id="development">

                     <transactionManager type="JDBC" />

                     <dataSource type="POOLED">

                           <property name="driver"

                                  value="oracle.jdbc.driver.OracleDriver" />

                           <property name="url"

                                  value="jdbc:oracle:thin:@localhost:1521:orcl" />

                           <property name="username" value="scott" />

                           <property name="password" value="tiger" />

                     </dataSource>

              </environment>

       </environments>

       <mappers>

              <mapper resource="BoardMapper.xml" />

       </mappers>

       

</configuration>

BoardMapper.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="BoardMapper">

       <select id="selectBoardToMap" parameterType="hashmap" resultType="hashmap">

              SELECT SEQ, TITLE, CONTENT , HIT_CNT

              FROM BOARD

              WHERE SEQ = #{SEQ}

       </select>

       <select id="selectBoardToBean" parameterType="Board" resultType="Board">

              SELECT SEQ, TITLE, CONTENT , HIT_CNT as hitcnt

              FROM BOARD

              WHERE SEQ = #{seq}   

                <!-- 파라미터로사용시 대소문자구분, result는  대소문자구분X -->

       </select>

       

</mapper>

BoardMapper.java    -- 매퍼.xml사용안하고 매퍼.class사용시

import org.apache.ibatis.annotations.Select;

/*     XML매퍼(BardMapper.xml)를 작성안해도됨

*

* */

public interface BoardMapper {

       @Select("SELECT "

                     + "SEQ, TITLE, CONTENT, HIT_CNT as hitcnt "

                     + "FROM BOARD "

                     + "WHERE SEQ = #{SEQ}")

       Board selectBoard(int seq);

}

Board.java

private int seq, hitCnt;

private String title,content;