[ 참고 강의 ] 실전! 스프링 부트와 JPA 활용1 - 웹 애플리케이션 개발
@Repository
@RequiredArgsConstructor
public class MemberRepository {
private final EntityManager em;
public void save(Member member) {
em.persist(member);
}
public Member findOne(Long id) {
return em.find(Member.class, id);
}
public List<Member> findAll() {
List<Member> result = em.createQuery("select m from Member m", Member.class)
.getResultList();
return result;
}
public List<Member> findByName(String name) {
return em.createQuery("select m from Member m where m.name = :name", Member.class)
.setParameter("name", name)
.getResultList();
}
}
@Service
@Transactional(readOnly = true)
@RequiredArgsConstructor
public class MemberService {
private final MemberRepository memberRepository;
//회원 가입
@Transactional
public Long join(Member member) {
validateDuplicateMember(member); //중복 회원 검
memberRepository.save(member);
return member.getId();
}
private void validateDuplicateMember(Member member) {
//EXCEPTION
List<Member> findMembers = memberRepository.findByName(member.getName());
if (!findMembers.isEmpty()) {
throw new IllegalStateException("이미 존재하는 회원입니다.");
}
}
//회원 전체 조회
public List<Member> findMembers() {
return memberRepository.findAll();
}
public Member findOne(Long memberId){
return memberRepository.findOne(memberId);
}
}
@RequiredArgsConstructor
public class MemberService {
private final MemberRepository memberRepository;
... }
final 키워드를 잡아서 생성자 주입을 시켜준다.
@RunWith(SpringRunner.class)
@SpringBootTest
@Transactional
public class MemberServiceTest {
@Autowired MemberService memberService;
@Autowired MemberRepository memberRepository;
@Autowired EntityManager em;
@Test
public void 회원가입() throws Exception {
//given
Member member = new Member();
member.setName("kim");
//when
Long savedId = memberService.join(member);
//then
assertEquals(member, memberRepository.findOne(savedId));
}
@Test(expected = IllegalStateException.class)
public void 중복_회원_에외() throws Exception {
//given
Member member1 = new Member();
member1.setName("kim");
Member member2 = new Member();
member2.setName("Kim");
//when
memberService.join(member1);
memberService.join(member2); //예외가 발생해야 한다!!!
//then
fail("예외가 발생해야 한다.");
}
}
상품 엔티티 코드
@Entity
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "dtype")
@Getter
public abstract class Item {
@Id @GeneratedValue
@Column(name = "item_id")
private Long id;
private String name;
private int price;
private int stockQuantity;
@ManyToMany(mappedBy = "items")
private List<Category> categories = new ArrayList<Category>();
//==비즈니스 로직==//
//stock 증가
public void addStock(int quantity) {
this.stockQuantity += quantity;
}
//stock 감소
public void removeStock(int quantity) {
int restStock = this.stockQuantity - quantity;
if (restStock < 0) {
throw new NotEnoughStockException("need more stock");
}
this.stockQuantity = restStock;
}
}
상품 리포지토리 코드
@Repository
@RequiredArgsConstructor
public class ItemRepository {
private final EntityManager em;
public void save(Item item) {
if(item.getId() == null) {
em.persist(item);
} else {
em.merge(item);
}
}
public Item findOne(Long id) {
return em.find(Item.class, id);
}
public List<Item> findAll() {
return em.createQuery("select i from Item i", Item.class)
.getResultList();
}
}
id가 없으면 신규로 보고 persist() 실행
id가 있으면 이미 데이터베이스에 저장된 엔티티를 수정한다고 보고, merge()를 실행
상품 서비스 코드
@Service
@Transactional(readOnly = true)
@RequiredArgsConstructor
public class ItemService {
private final ItemRepository itemRepository;
@Transactional
public void saveItem(Item item) {
itemRepository.save(item);
}
public List<Item> findItems() {
return itemRepository.findAll();
}
public Item findOne(Long itemId) {
return itemRepository.findOne(itemId);
}
}
다음은 핵심인 주문 기능에 대해 코드를 정리해보겠씁니다~