JPA 시작하기

프로젝트 생성

도커로 H2 생성

docker run -d -p 1521:1521 -p 81:81 -v D:\\database:/opt/h2-data -e H2_OPTIONS='-ifNotExists' --name=h2db oscarfonts/h2

난 도커를 사용

docker run -d -p 1521:1521 -p 81:81 -v D:\\database:/opt/h2-data -e H2_OPTIONS='-ifNotExists' --name=h2db oscarfonts/h2

PS D:\\downloads\\Kitematic-Windows> docker run -d -p 1521:1521 -p 81:81 -v D:\\database:/opt/h2-data -e H2_OPTIONS='-ifNotExists' --name=h2db oscarfonts/h2
63ad35bad70054b400a46a4439bb6566420473a070dca759b45bc15be3cca95d
PS D:\\downloads\\Kitematic-Windows> docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                                        NAMES
63ad35bad700        oscarfonts/h2       "/bin/sh -c 'java -c…"   4 seconds ago       Up 2 seconds        0.0.0.0:81->81/tcp, 0.0.0.0:1521->1521/tcp   h2db
PS D:\\downloads\\Kitematic-Windows>

메이븐 프로젝트 생성 및 의존성 추가

<dependencies>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>5.3.10.Final</version>
    </dependency>

    <dependency>
        <groupId>com.h2database</groupId>
        <artifactId>h2</artifactId>
        <version>1.4.199</version>
    </dependency>
</dependencies>

JPA 설정

JPA 설정 파일 • /META-INF/persistence.xml 위치 • persistence-unit name으로 이름 지정 • javax.persistence로 시작: JPA 표준 속성 • hibernate로 시작: 하이버네이트 전용 속성

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.2"
             xmlns="<http://xmlns.jcp.org/xml/ns/persistence>" xmlns:xsi="<http://www.w3.org/2001/XMLSchema-instance>"
             xsi:schemaLocation="<http://xmlns.jcp.org/xml/ns/persistence> <http://xmlns.jcp.org/xml/ns/persistence/persistence_2_2.xsd>">
    <persistence-unit name="hello">
        <properties>
            <!-- 필수 속성 -->
            <property name="javax.persistence.jdbc.driver" value="org.h2.Driver"/>
            <property name="javax.persistence.jdbc.user" value="sa"/>
            <property name="javax.persistence.jdbc.password" value=""/>
            <property name="javax.persistence.jdbc.url" value="jdbc:h2:tcp://localhost/~/test"/>
            <property name="hibernate.dialect" value="org.hibernate.dialect.H2Dialect"/>

            <!-- 옵션 -->
            <property name="hibernate.show_sql" value="true"/>
            <property name="hibernate.format_sql" value="true"/>
            <property name="hibernate.use_sql_comments" value="true"/>
            <!--<property name="hibernate.hbm2ddl.auto" value="create" />-->
        </properties>
    </persistence-unit>
</persistence>

그리고 일단 실행해보자.

package hellojpa;

import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;

public class JpaMain {
    public static void main(String[] args) {
        EntityManagerFactory emf = Persistence.createEntityManagerFactory("hello");
    }
}