회원 관리 예제 - 백엔드 개발

shift+F6 rename

ctrl+Alt+Shift+t refactor하기(그 중 Extract Method를 할 것임)

class에 커서 두고 ctrl+shift+t  자동으로 test코드 생성

ctrl+Alt+v asswertThrows를 IllegalStateException e로 바꿀 때 편함

shift+F10 이전 실행 다시

 

☆ 비즈니스 요구사항 정리

- 데이터 : 회원ID, 이름

- 기능 : 회원 등록, 조회

- 아직 데이터 저장소가 선정되지 않음(가상의 시나리오)

 

☆ 일반적인 웹 애플리케이션 계층 구조

 

컨트롤러 : 웹MVC의 컨트롤러 역할

서비스 : 핵심 비즈니스 로직 구현

리포지트리 : 데이터베이스에 접근, 도메인 객체를 DB에 저장, 관리

도메인 : 비즈니스 도메인 객체 ex) 회원, 주문, 쿠폰 등등 주로 데이터베이스에 저장하고 관리

 

package start.hellospring.repository;

import start.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();
    }

 

 

인터페이스 

 

package start.hellospring.repository;

import start.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();
    }

}

 

repository코드.

 

package start.hellospring.repository;

import org.assertj.core.api.Assertions;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.Test;
import start.hellospring.domain.Member;

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

import static org.assertj.core.api.AssertionsForClassTypes.assertThat;

public 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);
        Assertions.assertThat(member).isEqualTo(result);	//편하게 쓸 때 쓰자
    }

    @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);
    }

}

 

test코드.

각각의 테스트는 독립적이여야 하기 때문에 repository.clearStore() 메소드로 변수 초기화.(매우 중요한 과정)

 

package start.hellospring.service;

import start.hellospring.domain.Member;
import start.hellospring.repository.MemberRepository;
import start.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;
    }

    //회원가입
    public Long join(Member member){
        // 같은 이름이 있는 중복 회원x
        validateDuplicateMember(member);    // 중복 회원 검증
        memberRepository.save(member);
        return member.getId();
    }

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

    // 전체 회원 조회
    public List<Member> findMembers(){
        return memberRepository.findAll();
    }

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

 

package start.hellospring.service;

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 start.hellospring.domain.Member;
import start.hellospring.repository.MemoryMemberRepository;

import java.util.Optional;

import static org.assertj.core.api.AssertionsForClassTypes.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 saveId = memberService.join(member);

        //then
        Member findMember=memberService.findOne(saveId).get();
        Assertions.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);
        //assertThrows(IllegalStateException.class, ()->memberService.join(member2));
        IllegalStateException e = assertThrows(IllegalStateException.class, () -> memberService.join(member2));
        assertThat(e.getMessage()).isEqualTo("이미 존재하는 회원입니다.");

      /*  try{
            memberService.join(member2);
            fail();
        } catch(IllegalStateException e){
            assertThat(e.getMessage()).isEqualTo("이미 존재하는 회원입니다.");
        }*/
        //then
    }

    @Test
    void findMembers() {
    }

    @Test
    void findOne() {
    }
}

 

@BeforeEach로 MemberService.java와 같은 memberRepository를 쓰도록 함.