H2 데이터베이스 설치
1.4.200 버전 다운로드
나는 윈도우 유저라 h2.bat으로 접속
jdbc:h2:tcp://localhost/~/test 으로 소켓사용해서 접근
create table member
(
id bigint generated by default as identity,
name varchar(255),
primary key (id)
);db생성! generated by default as identity(db가 자동으로 채워줌)
여기서 갑자기 INSERT INTO 할 때 오류생겨서 당황했었는데 "를 '로 변경하니까 되더라 ;;;;;
순수 JDBC
build.gradle에 라이브러리 추가
application.properties에 또 추가 ( 나는 저번에 server port 9090으로 변경해줬었음 )
고대의 방식으로 배워보는 시간~~
package hello.hellospring.repository;
import hello.hellospring.domain.Member;
import org.springframework.jdbc.datasource.DataSourceUtils;
import javax.sql.DataSource;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
public class JdbcMemberRepository implements MemberRepository {
private final DataSource dataSource;
public JdbcMemberRepository(DataSource dataSource) {
this.dataSource = dataSource;
}
@Override
public Member save(Member member) {
String sql = "insert into member(name) values(?)";
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null; //결과 받기
try {
conn = getConnection();
pstmt = conn.prepareStatement(sql,
Statement.RETURN_GENERATED_KEYS); //맨뒤 옵션 -> insert 해주는 옵션임
pstmt.setString(1, member.getName());
pstmt.executeUpdate();
rs = pstmt.getGeneratedKeys();
if (rs.next()) {
member.setId(rs.getLong(1));
} else {
throw new SQLException("id 조회 실패");
}
return member;
} catch (Exception e) {
throw new IllegalStateException(e);
} finally {
close(conn, pstmt, rs);
}
}
@Override
public Optional<Member> findById(Long id) {
String sql = "select * from member where id = ?";
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try {
conn = getConnection();
pstmt = conn.prepareStatement(sql);
pstmt.setLong(1, id);
rs = pstmt.executeQuery();
if(rs.next()) {
Member member = new Member();
member.setId(rs.getLong("id"));
member.setName(rs.getString("name"));
return Optional.of(member);
} else {
return Optional.empty();
}
} catch (Exception e) {
throw new IllegalStateException(e);
} finally {
close(conn, pstmt, rs);
}
}
@Override
public List<Member> findAll() {
String sql = "select * from member";
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try {
conn = getConnection();
pstmt = conn.prepareStatement(sql);
rs = pstmt.executeQuery();
List<Member> members = new ArrayList<>();
while(rs.next()) {
Member member = new Member();
member.setId(rs.getLong("id"));
member.setName(rs.getString("name"));
members.add(member);
}
return members;
} catch (Exception e) {
throw new IllegalStateException(e);
} finally {
close(conn, pstmt, rs);
}
}
@Override
public Optional<Member> findByName(String name) {
String sql = "select * from member where name = ?";
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try {
conn = getConnection();
pstmt = conn.prepareStatement(sql);
pstmt.setString(1, name);
rs = pstmt.executeQuery();
if(rs.next()) {
Member member = new Member();
member.setId(rs.getLong("id"));
member.setName(rs.getString("name"));
return Optional.of(member);
}
return Optional.empty();
} catch (Exception e) {
throw new IllegalStateException(e);
} finally {
close(conn, pstmt, rs);
}
}
private Connection getConnection() {
return DataSourceUtils.getConnection(dataSource); //utils를 통해서 커넥션해야 transaction
}
private void close(Connection conn, PreparedStatement pstmt, ResultSet rs)
{
try {
if (rs != null) {
rs.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
try {
if (pstmt != null) {
pstmt.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
try {
if (conn != null) {
close(conn);
}
} catch (SQLException e) {
e.printStackTrace();
}
}
private void close(Connection conn) throws SQLException {
DataSourceUtils.releaseConnection(conn, dataSource);
}
}코드가 대박 와방 김 ~
스프링 통합 테스트
package hello.hellospring.service;
import hello.hellospring.domain.Member;
import hello.hellospring.repository.MemberRepository;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.transaction.annotation.Transactional;
import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertThrows;
@SpringBootTest //이거 한줄로 다 해결됨 .. 댑악임
@Transactional
class MemberServiceIntegrationTest {
@Autowired MemberService memberService;
@Autowired MemberRepository memberRepository;
//afterEach 필요없음
@Test
public void 회원가입() throws Exception {
//Given
Member member = new Member();
member.setName("hello");
//When
Long saveId = memberService.join(member);
//Then
Member findMember = memberRepository.findById(saveId).get();
assertEquals(member.getName(), findMember.getName());
}
@Test
public void 중복_회원_예외() throws Exception {
//Given
Member member1 = new Member();
member1.setName("spring");
Member member2 = new Member();
member2.setName("spring");
//When
memberService.join(member1);
IllegalStateException e = assertThrows(IllegalStateException.class,
() -> memberService.join(member2));//예외가 발생해야 한다.
assertThat(e.getMessage()).isEqualTo("이미 존재하는 회원입니다.");
}
}@Transactional -> 트랜잭션을 먼저 시작하고 완료 후에 항상 롤백, DB에 데이터가 안남아서 다음 테스트시 아주 클린하당
스프링 JdbcTemplate
이 템플릿은 반복코드 제거에 아쥬 탁월함.
package hello.hellospring.repository;
import hello.hellospring.domain.Member;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import org.springframework.jdbc.core.namedparam.MapSqlParameterSource;
import org.springframework.jdbc.core.simple.SimpleJdbcInsert;
import javax.sql.DataSource;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
public class JdbcTemplateMemberRepository implements MemberRepository {
private final JdbcTemplate jdbcTemplate;
//생성자가 한개면 @Autowired같은 빈 생략 가능
public JdbcTemplateMemberRepository(DataSource dataSource) {
jdbcTemplate = new JdbcTemplate(dataSource);
}
@Override
public Member save(Member member) {
SimpleJdbcInsert jdbcInsert = new SimpleJdbcInsert(jdbcTemplate);
jdbcInsert.withTableName("member").usingGeneratedKeyColumns("id");
Map<String, Object> parameters = new HashMap<>();
parameters.put("name", member.getName());
Number key = jdbcInsert.executeAndReturnKey(new
MapSqlParameterSource(parameters));
member.setId(key.longValue());
return member;
}
@Override
public Optional<Member> findById(Long id) {
List<Member> result = jdbcTemplate.query("select * from member where id = ?", memberRowMapper(), id);
return result.stream().findAny();
}
@Override
public List<Member> findAll() {
return jdbcTemplate.query("select * from member", memberRowMapper());
}
@Override
public Optional<Member> findByName(String name) {
List<Member> result = jdbcTemplate.query("select * from member where name = ?", memberRowMapper(), name);
return result.stream().findAny();
}
private RowMapper<Member> memberRowMapper() {
return (rs, rowNum) -> {
Member member = new Member();
member.setId(rs.getLong("id"));
member.setName(rs.getString("name"));
return member;
};
}
}몇줄만에 어마어마하게 긴 내용을 축약 가능한 매우매우 편리한 기능
JPA
템플릿을 사용해서 편하게 작성할 수는 있었으나 결국 sql은 짜줘야했었는데 ... JPA(인터페이스)는 쿼리도 자기가 짜줌 .. (👼)
spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=none
를 추가해준다 ddl-auto에서 어떤 값을 지정하는지에 따라서 자동으로 그 단계까지 해줌
ORM(Object-Relational-Mapping) - 객체와 관계형 데이터베이스를 자동으로 연결해주는 기능
package hello.hellospring.repository;
import hello.hellospring.domain.Member;
import javax.persistence.EntityManager;
import java.util.List;
import java.util.Optional;
public class JpaMemberRepository implements MemberRepository{
private final EntityManager em;
public JpaMemberRepository(EntityManager em) {
this.em = em;
}
public Member save(Member member) {
em.persist(member); //영구저장
return member;
}
public Optional<Member> findById(Long id) {
Member member = em.find(Member.class, id);
return Optional.ofNullable(member);
}
public List<Member> findAll() {
return em.createQuery("select m from Member m", Member.class)
.getResultList();
}
public Optional<Member> findByName(String name) {
List<Member> result = em.createQuery("select m from Member m where m.name = :name", Member.class)
.setParameter("name", name)
.getResultList();
return result.stream().findAny();
}
}SpringConfig는 다음과 같이 수정
package hello.hellospring;
import hello.hellospring.repository.JdbcTemplateMemberRepository;
import hello.hellospring.repository.JpaMemberRepository;
import hello.hellospring.repository.MemberRepository;
import hello.hellospring.service.MemberService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import javax.persistence.EntityManager;
import javax.sql.DataSource;
@Configuration
public class SpringConfig {
private EntityManager em;
@Autowired
public SpringConfig(EntityManager em) {
this.em = em;
}
/*private final DataSource dataSource;
public SpringConfig(DataSource dataSource) {
this.dataSource = dataSource;
}*/
@Bean
public MemberService memberService() {
return new MemberService(memberRepository());
}
@Bean
public MemberRepository memberRepository() {
// return new MemoryMemberRepository();
// return new JdbcMemberRepository(dataSource);
return new JpaMemberRepository(em);
}
}//오류가 도저히 해결이 안되어서 중단
너무 슬픈게 ... Bean이랑 다른거랑 충돌되서 일어나는 것 같은데 .. 아직도 연유를 알수가 없음 ㅠ ㅠ
스프링 데이터 JPA
여전히 안됨 ............. exit 0으로 나감 ㅠ ㅠ .. 진짜 짜증나 . .울굎어
