[스프링 입문] 회원 관리 예제

단축키

• Alt + Enter : 가장 기본적이고 많이 사용하는 단축키. 일단 귀찮을 것 같은 코드에 쓰면 도움이 됨.
• Ctrl + Alt + V : 선택한 코드들을 Method 형식으로 바꿔줌.
• Shift + F6 : 이름 전체 변경.
• Ctrl + Shift + Enter : 현재 구문 완성.
• Alt + insert : Getter / Setter 자동 완성

일반적인 웹 애플리케이션 계층 구조

회원 관리 예제 비지니스 요구사항

• 데이터 - 회원ID,이름
• 기능 - 회원 등록, 조회
• 데이터 저장소 선정 X

클래스 의존관계

• 데이터 저장소 선정 X -> 인터페이스로 구현 클래스 설계

회원 도메인, 리포지토리 만들기

도메인

• hello.hellospring 에 domain package 생성.
• Member 자바 클래스 생성

package hello.hellospring.domain;

public class Member {
    private Long id;
    private String name;

    public void setName(String name) {
        this.name = name;
    }

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

    public String getName() {
        return name;
    }

리포지토리

• hello.hellospring 에 repository package 생성.
• MemberRepository 인터페이스 생성

package hello.hellospring.repository;

import hello.hellospring.domain.Member;

import java.util.List;
import java.util.Optional;

public interface MemberRepository {
    Member save(Member member);
    Optional<Member> findById(Long id);
    Optional<Member> findByName(String name);
    List<Member> findAll();
}

리포지토리 메모리 구현체

• MemoryMemberRepository 자바 클래스 생성

package hello.hellospring.repository;

import hello.hellospring.domain.Member;

import java.util.*;

public class MemoryMemberRepository implements  MemberRepository{

    private static Map<Long,Member> store = new HashMap<>();
    private static long sequence= 0L;

    @Override
    public Member save(Member member) {
        member.setId(++sequence);
        store.put(member.getId(),member);
        return member;
    }

    @Override
    public Optional<Member> findById(Long id) {
        return Optional.ofNullable(store.get(id));
    }

    @Override
    public Optional<Member> findByName(String name) {
        return store.values().stream()
                .filter(member -> member.getName().equals(name))
                .findAny();
    }

    @Override
    public List<Member> findAll() {
        return new ArrayList<>(store.values());
    }
    public void clearStore(){
        store.clear();
    }
}

테스트 케이스 작성

• src/test/java 에 작성.
• @Test 사용
• @AfterEach 로 저장된 데이터 삭제.
• assertThat은 테스트 코드에서 예상 값과 실제 값이 일치하는지를 검증하는 데 사용됨.
• 각 테스트마다 clear 해줘야 함 (중요)

package hello.hellospring.repository;

import hello.hellospring.domain.Member;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

import java.util.List;
import java.util.Optional;

import static org.assertj.core.api.Assertions.as;
import static org.assertj.core.api.Assertions.assertThat;

class MemoryMemberRepositoryTest {
    MemoryMemberRepository repository = new MemoryMemberRepository();

    @AfterEach
    public void afterEach(){
        repository.clearStore();
    }

    @Test
    public void save(){
        Member member = new Member();
        member.setName("spring");

        repository.save(member);

        Member result = repository.findById(member.getId()).get();
        //Assertions.assertEquals(member,result);
        assertThat(member).isEqualTo(result);
    }

    @Test
    public void findByName(){
        Member member1 = new Member();
        member1.setName("spring1");
        repository.save(member1);

        Member member2 = new Member();
        member2.setName("spring2");
        repository.save(member2);

        Member result = repository.findByName("spring1").get();

        assertThat(result).isEqualTo(member1);

    }

    @Test
    public void findAll(){
        Member member1 = new Member();
        member1.setName("spring1");
        repository.save(member1);

        Member member2 = new Member();
        member2.setName("spring2");
        repository.save(member2);

        List<Member> result = repository.findAll();
        assertThat(result.size()).isEqualTo(2);
    }
}

회원 서비스 개발

package hello.hellospring.service;

import hello.hellospring.domain.Member;
import hello.hellospring.repository.MemberRepository;
import hello.hellospring.repository.MemoryMemberRepository;

import java.util.List;
import java.util.Optional;

public class MemberService {
    private final MemberRepository memberRepository;

    public MemberService(MemberRepository memberRepository) {
        this.memberRepository = memberRepository;
    }


    public Long join(Member member){
        validateDuplicateMember(member);
        memberRepository.save(member);
        return member.getId();
    }

    private void validateDuplicateMember(Member member) {
        memberRepository.findByName(member.getName())
                        .ifPresent(m->{
                            throw new IllegalStateException("이미 존재하는 회원입니다.");
                        });
    }

    public List<Member> findMember(){
        return memberRepository.findAll();
    }

    public Optional<Member> findOne(Long memberId){
        return memberRepository.findById(memberId);
    }
}

회원 서비스 테스트

• @BeforeEach 각 테스트 실행 전 호출.
• @AfterEach 각 테스트 실행 후 호출. 일종의 콜백함수.
• 테스트에선 Method 이름을 한글로 작성해도 무관.

package hello.hellospring.service;

import hello.hellospring.domain.Member;
import hello.hellospring.repository.MemoryMemberRepository;
import org.assertj.core.api.Assertions;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

import java.util.Optional;

import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.jupiter.api.Assertions.*;

class MemberServiceTest {

    MemberService memberService;
    MemoryMemberRepository memberRepository;

    @BeforeEach
    public void beforeEach(){
        memberRepository = new MemoryMemberRepository();
        memberService = new MemberService(memberRepository);
    }
    @AfterEach
    public void afterEach(){
        memberRepository.clearStore();
    }

    @Test
    void 회원가입() {
        //given
        Member member = new Member();
        member.setName("hello");
        //when
        Long id = memberService.join(member);

        //then
        Member findMember = memberService.findOne(id).get();
        assertThat(member.getName()).isEqualTo(findMember.getName());
    }

    @Test
    public void 중복_회원_예외(){
        //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));
        assertThat(e.getMessage()).isEqualTo("이미 존재하는 회원입니다.");
        //then
    }

    @Test
    void findMember() {
    }

    @Test
    void findOne() {
    }
}