Spring core 회원도메인 (김영한의 스프링)

 

 

회원도메인 개발

 

 

회원 엔티티 ->  ① enum Grade(회원 등급)

                             ② class Member(멤버 구성)

 

 

▶ enum Grade 회원등급을 상수열거형으로 정리한 enum class

 

package hello.core.member;
 
public enum Grade {
    BASIC,
    VIP
 
}

▶ Member class 회원 객체를 나타내는 Java class

 

package hello.core.member;
 
public class Member {
    private Long id;
    private String name;
    private Grade grade;
    public Member(Long id, String name, Grade grade) {
        this.id = id;
        this.name = name;
        this.grade = grade;
    }
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Grade getGrade() {
        return grade;
    }
    public void setGrade(Grade grade) {
        this.grade = grade;
    }
}

 

 

 

회원 저장소 ->  ① interface MemberRepository(회원 저장소 인터페이스)

                            ② class MemoryMemberRepository(메모리 회원 저장소 구현체)

 

 

▶ interface MemberRepository 회원정보 저장조회 회원관리 리포지토리

 

package hello.core.member;
public interface MemberRepository {
    void save(Member member);
    Member findById(Long memberId);
}

 

▶ 위에 interface를 구현한 class MemoryMemberRepository 회원 저장소

 

save(Member member) 메서드:
Member 객체를 저장하는 메서드입니다.
store 맵에 member.getId()를 키로 하고, member 객체를 값으로 저장합니다.
이렇게 저장하면 회원의 고유 ID를 활용하여 회원 정보를 저장하고 검색할 수 있습니다.

 

findById(Long memberId) 메서드:
주어진 memberId에 해당하는 회원 정보를 조회하는 메서드입니다.
store 맵에서 memberId를 키로하여 해당 회원 정보를 가져옵니다.
만약 해당하는 회원이 없으면 null을 반환합니다.

 

package hello.core.member;
import java.util.HashMap;
import java.util.Map;
public class MemoryMemberRepository implements MemberRepository {
    private static Map<Long, Member> store = new HashMap<>();
    @Override
    public void save(Member member) {
        store.put(member.getId(), member);
    }
    @Override
    public Member findById(Long memberId) {
        return store.get(memberId);
    }
}

 

 

 

회원서비스 ->  ① interface MemberService(회원서비스인터페이스)

                           ② class MemberServiceImpl(회원서비스구현체)

 

 

 

▶ interface MemberService 회원에 대한 서비스 정의 인터페이스

 

package hello.core.member;
public interface MemberService {
    void join(Member member);
    Member findMember(Long memberId);
}

 

▶ 위에 interface를 구현한 class MemberServiceImpl 회원 관리

 

package hello.core.member;
 
 
public class MemberServiceImpl implements MemberService{
 
    private final MemberRepository memberRepository = new MemoryMemberRepository();
    @Override
    public void join(Member member) {
        memberRepository.save(member);
    }
 
    @Override
    public Member findMember(Long memberId) {
        return memberRepository.findById(memberId);
    }
}

 

 

 

＃회원 도메인 실행과 테스트

회원 도메인 - 회원 가입 main

회원 정보를 생성하고 조회하는 기능을 포함하고 있습니다.

메인 애플리케이션 클래스로, 회원 등록과 조회를 수행합니다.

 

 

정보초기화를 위해

 Member member = new Member(1L, "memberA", Grade.VIP) ;

-> 회원아이디 : 1L, 회원이름: "memberA", 등급: Grade.VIP 

memberService.join(member);

-> 호출해서 회원등록(가입) 시킵니다.

Member findMember = memberService.findMember(1L);

-> 호출해서 가입한 member 아이디 찾아서 결과 출력

 

package hello.core;
 
import ch.qos.logback.core.net.SyslogOutputStream;
import hello.core.member.Grade;
import hello.core.member.Member;
import hello.core.member.MemberService;
import hello.core.member.MemberServiceImpl;
 
public class MemberApp {
    public static void main(String[] args) {
        MemberService memberService = new MemberServiceImpl();
        Member member = new Member(1L, "memberA", Grade.VIP);
        memberService.join(member);
 
        Member findMember = memberService.findMember(1L);
        System.out.println("new Member = " + member.getName());
        System.out.println("find Member = " + findMember.getName());
    }
 
}

 

회원 Test(Unit Test) 

 

Assertions.assertThat(member).isEqualTo(findMember);

-> Assertions는 AssertJ라는 자바라이브러리 객체 비교 및 검증하는 메서드입니다. 주로 Test할때 사용

    assertThat은 테스트코드에서 예상값과 실제값을 비교할때 사용합니다.

 

package hello.core.member;
 
import org.assertj.core.api.Assertions;
import org.junit.jupiter.api.Test;
 
public class MemberServiceTest {
 
    MemberService memberService = new MemberServiceImpl();
 
    @Test
    void join() {
 
        //given
        Member member = new Member(1L, "memberA", Grade.VIP);
 
        // when
        memberService.join(member);
        Member findMember = memberService.findMember(1L);
 
        // then
        Assertions.assertThat(member).isEqualTo(findMember);
 
    }
 
}

 

 

 

 

 

# 주문과 할인

 

▶ interface DiscountPolicy 

인터페이스를 활용하면 여러 가지 다른 할인 정책을 쉽게 추가하고 변경할 수 있으며, 

다형성을 활용하여 다양한 할인 정책을 사용할 수 있게 됩니다.

 

package hello.core.discount;
 
import hello.core.member.Member;
 
public interface DiscountPolicy {
 
    /**
     *
     * @param member
     * @param price
     * @return 할인 대상 금액
     */
    int discount(Member member, int price);
}

 

 

 

▶ class FixDiscountPolicy

discount 메서드

만약 회원의 등급이 VIP인 경우, 고정된 할인 금액인 discountFixAmount (1000원)을 반환합니다.

VIP 회원에게는 항상 1000원의 할인이 적용됩니다.
그 외의 경우 (일반 회원인 경우), 할인이 적용되지 않으므로 0을 반환합니다.

 

package hello.core.discount;
 
import hello.core.member.Grade;
import hello.core.member.Member;
 
public class FixDiscountPolicy implements DiscountPolicy{
 
    private int discountFixAmount = 1000; // 1000원 할인
    @Override
    public int discount(Member member, int price) {
        if(member.getGrade() == Grade.VIP){
            return discountFixAmount;
        } else {
            return 0;
 
        }
    }
}

 

 

 

▶ 엔티티 Order

calculatePrice(): 주문한 상품의 가격에서 할인된 가격을 빼서 최종 가격을 계산하는 메서드입니다.

이 메서드는 itemPrice에서 discountPrice를 빼서 최종 가격을 반환합니다.

 

package hello.core.order;
 
public class Order {
 
    private Long memberId;
    private String itemName;
    private int itemPrice;
    private int discountPrice;
 
    public Order(Long memberId, String itemName, int itemPrice, int discountPrice) {
        this.memberId = memberId;
        this.itemName = itemName;
        this.itemPrice = itemPrice;
        this.discountPrice = discountPrice;
    }
 
    public int calculatePrive(){
        return itemPrice - discountPrice;
    }
 
    public Long getMemberId() {
        return memberId;
    }
 
    public void setMemberId(Long memberId) {
        this.memberId = memberId;
    }
 
    public String getItemName() {
        return itemName;
    }
 
    public void setItemName(String itemName) {
        this.itemName = itemName;
    }
 
    public int getItemPrice() {
        return itemPrice;
    }
 
    public void setItemPrice(int itemPrice) {
        this.itemPrice = itemPrice;
    }
 
    public int getDiscountPrice() {
        return discountPrice;
    }
 
    public void setDiscountPrice(int discountPrice) {
        this.discountPrice = discountPrice;
    }
 
    @Override
    public String toString() {
        return "Order{" +
                "memberId=" + memberId +
                ", itemName='" + itemName + '\'' +
                ", itemPrice=" + itemPrice +
                ", discountPrice=" + discountPrice +
                '}';
    }
}

 

 

 

 

▶ interface OrderService(주문서비스 인터페이스)

createOrder(Long memberId, String itemName, int itemPrice): 이 메서드는 주문을 생성하는데 필요한 정보를 받아서 주문을 생성하고, 생성된 주문 객체를 반환하는 역할을 합니다. 

주문 생성에 필요한 정보로는 회원 ID (memberId), 상품 이름 (itemName), 상품 가격 (itemPrice)이 필요합니다. 

이 메서드는 이러한 정보를 받아서 새로운 주문 객체(Order)를 생성하고 반환합니다.

 

package hello.core.order;
 
public interface OrderService {
    Order createOrder(Long memberId, String itemName, int itemPrice);
}

 

 

 

 

▶ class OrderServiceImpl(주문 생성에 관한 구체적인 로직을 포함)

회원 정보는 MemberRepository를 통해 조회하고, 할인 정책은 DiscountPolicy에 의해 적용됩니다.
주문 생성 시 할인된 가격이 계산되어 Order 객체에 저장됩니다.

 

Order createOrder메서드는

Member member = memberRepository.findById(memberId);: 주문을 생성하기 위해 주어진 memberId를 사용하여 memberRepository에서 해당 회원 정보를 조회합니다.

int discountPrice = discountPolicy.discount(member, itemPrice);: discountPolicy를 사용하여 할인 금액을 계산합니다. member는 주문한 회원 정보이고, itemPrice는 주문한 상품의 가격입니다.

 

package hello.core.order;
 
import hello.core.discount.DiscountPolicy;
import hello.core.discount.FixDiscountPolicy;
import hello.core.member.Member;
import hello.core.member.MemberRepository;
import hello.core.member.MemoryMemberRepository;
 
public class OrderServiceImpl implements OrderService{
 
    private final MemberRepository memberRepository = new MemoryMemberRepository();
    private final DiscountPolicy discountPolicy = new FixDiscountPolicy();
 
    @Override
    public Order createOrder(Long memberId, String itemName, int itemPrice) {
        Member member = memberRepository.findById(memberId);
        int discountPrice = discountPolicy.discount(member, itemPrice);
 
        return new Order(memberId, itemName, itemPrice, discountPrice);
    }
}

 

# 주문과 할인 도메인 실행과 테스트

 

 

 

▶ class OrderApp(회원 가입과 주문 생성을 시뮬레이션하는 간단한 프로그램)

MemberService와 OrderService 인터페이스를 구현한 MemberServiceImpl과 OrderServiceImpl 클래스가 사용됩니다. 이 서비스 클래스들은 회원과 주문 관련 기능을 제공합니다.

Member 객체를 생성하고 회원 가입을 시뮬레이션합니다. 이 회원은 VIP 등급인 "memberA"로 가입됩니다.

OrderService의 createOrder 메서드를 호출하여 주문을 생성합니다. 이 메서드는 회원 ID, 상품 이름, 상품 가격을 인자로 받아 주문 객체를 생성하고 반환합니다.

생성된 주문 객체를 출력하여 확인합니다.

 

package hello.core;
 
import hello.core.member.Grade;
import hello.core.member.Member;
import hello.core.member.MemberService;
import hello.core.member.MemberServiceImpl;
import hello.core.order.Order;
import hello.core.order.OrderService;
import hello.core.order.OrderServiceImpl;
 
public class OrderApp {
 
    public static void main(String[] args) {
        MemberService memberService = new MemberServiceImpl();
        OrderService orderService = new OrderServiceImpl();
 
        Long memberId = 1L;
        Member member = new Member(memberId, "memberA", Grade.VIP);
        memberService.join(member);
 
        Order order = orderService.createOrder(memberId, "itemA", 10000);
 
        System.out.println("order = " + order);
 
    }
}

 

 

 

▶ OrderServiceTest

MemberService 및 OrderService를 생성하고, 

createOrder 메서드의 테스트를 위해 각 서비스에 대한 인스턴스를 생성합니다.

 

createOrder 테스트 메서드는 다음과 같은 단계로 구성됩니다:
회원을 생성하고 VIP 등급인 "memberA"로 등록합니다.

orderService.createOrder 메서드를 호출하여 주문을 생성합니다. 

이 주문은 "itemA"라는 상품을 가격 10,000으로 생성합니다.

Assertions.assertThat을 사용하여 생성된 주문의 할인 가격(discountPrice)이 1,000과 같은지를 검사합니다. 이 부분에서는 VIP 회원에게 1,000원의 할인이 적용되어야 합니다.

 

package hello.core.order;
 
import hello.core.member.Grade;
import hello.core.member.Member;
import hello.core.member.MemberService;
import hello.core.member.MemberServiceImpl;
import org.assertj.core.api.Assertions;
import org.junit.jupiter.api.Test;
 
public class OrderServiceTest {
 
    MemberService memberService = new MemberServiceImpl();
    OrderService orderService = new OrderServiceImpl();
 
    @Test
    void createOrder(){
        Long memberId = 1L;
        Member member = new Member(memberId, "memberA", Grade.VIP);
        memberService.join(member);
 
        Order order = orderService.createOrder(memberId, "itemA", 10000);
        Assertions.assertThat(order.getDiscountPrice()).isEqualTo(1000);
    }
 
}