인프런 커뮤니티 질문&답변

[질문 템플릿]
1. 강의 내용과 관련된 질문인가요? (예)
2. 인프런의 질문 게시판과 자주 하는 질문에 없는 내용인가요? (예)
3. 질문 잘하기 메뉴얼을 읽어보셨나요? (예)

[질문 내용]
여기에 질문 내용을 남겨주세요.

 

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
private String id;

위 코드 작성 후 오류가 납니다.. String 말고 숫자로 해도 오류가 나네요 ㅠ ..

mysql로 바꿨는데 왜 그런지 모르겠습니다ㅠ

 

오류

 

 

 

 

member

package hellojpa;

import javax.persistence.*;
import java.math.BigDecimal;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.util.Date;

@Entity
public class Member {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private String id;

    @Column(name = "name", nullable = false)
    private String username;

    public Member(){

    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }
}

 

 

 

jpaMain

package hellojpa;

import org.hibernate.internal.build.AllowSysOut;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.EntityTransaction;
import javax.persistence.Persistence;
import java.util.List;

public class JpaMain {

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

        EntityManager em = emf.createEntityManager();

        EntityTransaction tx = em.getTransaction();
        tx.begin();

        try{

            Member member = new Member();
            //member.setId("ID_A");
            member.setUsername("C");

            em.persist(member);

            tx.commit();

        }catch (Exception e){
            tx.rollback();
        }finally {
            em.close();
        }
        emf.close();



    }

}

persistence.xml

<?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.MySQL5Dialect"/>

            <!-- 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>