3. 회원 관리 예제 - 백엔드 개발

 

 

 

 

 

 

1. 비지니스 요규 사항 정리

• 데이터: 회원ID, 이름
• 기능: 회원 등록, 조회
• db없는 가상 시나리오

 

 

 

 

 

 

 

 

2. 회원 도메인과 리포지토리 만들기

 

1. "hello.hello_spring.domain" 패키지 만들기

• "member" class 만들기

package hello.hello_spring.domain;

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

    public Long getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }
}

 

 

 

 

 

2. "hello.hello_spring.repository" 패키지 만들기

• "MemberRepository" 인터페이스 만들기

package hello.hello_spring.repository;

import hello.hello_spring.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();
}

 

 

• "MemoryMemberRepository" class 만들기

package hello.hello_spring.repository;

import hello.hello_spring.domain.Member;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.ArrayList;

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));
    }

    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());
    }
}

 

 

 

 

 

 

 

 

 

3. 회원 리포지토리 테스트 케이스 작성 - test

• "hello.hello_spring.repository" 패키지 만들기
• "MemoryMemberRepositoryTest" 클래스 만들기

package hello.hello_spring.repository;

import hello.hello_spring.domain.Member;
import org.junit.jupiter.api.Test;

class MemoryMemberRepositoryTest {

    MemoryMemberRepository repository = new MemoryMemberRepository();

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

        repository.save(member);

        Member result = repository.findById(member.getId()).get();
        System.out.println("result =" + (result == member));
    }
}

 

 

• "MemoryMemberRepository" class 만들기

package hello.hello_spring.repository;

import hello.hello_spring.domain.Member;
import org.junit.jupiter.api.Test;

import java.util.List;

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

class MemoryMemberRepositoryTest {

    MemoryMemberRepository repository = new MemoryMemberRepository();

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

        repository.save(member);

        Member result = repository.findById(member.getId()).get();
        //System.out.println("result =" + (result == member));
        //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);
    }
}

 

하나씩 돌릴 떄는 괜찮은데, 한꺼번에 돌리려고 하닌까 오류가 난다.

 

 

 

 

1. 에러가 나는 이유

• test는 순서와 상관없이 매서드 별로 실행이 된다. 
• test하나가 끝나면 데이터를 clear해야 한다.

 

"MemoryMemberRepository.java" 추가

(...)
public void clearStore(){
        store.clear();
    }
(...)

 

 

"MemoryMemberRepositoryTest.java"

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

 

 

 

 

2. 전체 코드

• "MemoryMemberRepository.java"

package hello.hello_spring.repository;

import hello.hello_spring.domain.Member;

import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Optional;
import java.util.ArrayList;

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));
    }

    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();
    }
}

 

 

 

 

• "MemoryMemberRepositoryTest.java"

package hello.hello_spring.repository;

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

import java.util.List;

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

class MemoryMemberRepositoryTest {

    MemoryMemberRepository repository = new MemoryMemberRepository();

    // 테스트가 끝날때마다 clear해야 한다. test가 끝날때 마다 호출이 된다.
    @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();
        //System.out.println("result =" + (result == member));
        //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);
    }
}

 

 

 

 

 

4. 회원 서비스 개발

• "hello.hello_spring.service" 패키지 만들기
• "MemberService" class만들기

package hello.hello_spring.service;

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

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

public class MemberService {

    private final MemberRepository memberRepository = new MemoryMemberRepository();

    //
    public Long join(Member member) {

        validateDuplicateMember(member);  // 중복 회원 검증
        memberRepository.save(member);
        return member.getId();
    }

    // 회원가입
    public void validateDuplicateMember(Member member){

        /*
        //같은 이름이 있는 중복 회원x
        Optional<Member> result = memberRepository.findByName(member.getName());
        result.ifPresent(m -> {
            throw new IllegalStateException("이미 존재하는 회원힙니다.");
        });
         */
        //같은 이름이 있는 중복 회원x
        memberRepository.findByName(member.getName())
                .ifPresent(m -> {
                    throw new IllegalStateException("이미 존재하는 회원힙니다.");
                });

    }

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

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

 

 

 

 

 

 

 

5. 회원 서비스 테스트

• 테스트 하기: Ctrl + Shift + T
• "MemberServiceTest.java"

package hello.hello_spring.service;

import hello.hello_spring.domain.Member;
import hello.hello_spring.repository.MemoryMemberRepository;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

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




class MemberServiceTest {

    //MemberService memberService = new MemberService();
    //MemoryMemberRepository memberRepository = new MemoryMemberRepository();



    MemberService memberService ;
    MemoryMemberRepository memberRepository ;

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






    // 테스트가 끝날때마다 clear해야 한다. test가 끝날때 마다 호출이 된다.
    @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();
        assertThat(member.getName()).isEqualTo(findMember.getName());
    }

    @Test
    public void 중복회원예외() {
        // 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 회원힙니다.");

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

        //then
    }

    @Test
    void findMembers() {
    }

    @Test
    void findOne() {
    }
}

 

• "MemberService.java"

package hello.hello_spring.service;

import hello.hello_spring.domain.Member;
import hello.hello_spring.repository.MemberRepository;

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);  // 중복 회원 검증
        memberRepository.save(member);
        return member.getId();
    }

    // 회원가입
    public void validateDuplicateMember(Member member){

        /*
        //같은 이름이 있는 중복 회원x
        Optional<Member> result = memberRepository.findByName(member.getName());
        result.ifPresent(m -> {
            throw new IllegalStateException("이미 존재하는 회원힙니다.");
        });
         */
        //같은 이름이 있는 중복 회원x
        memberRepository.findByName(member.getName())
                .ifPresent(m -> {
                    throw new IllegalStateException("이미 존재하는 회원힙니다.");
                });

    }

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

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

 

 

 

 

 

---

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