5. [Spring] AppConfig 리팩터링

현재 AppConfig를 보면 "중복"이 있고, "역할"에 따른 "구현"이 잘 안보인다.

 

"기대하는 그림"

"리팩터링 전"

package hello.core;

import hello.core.discount.FixDiscountPolicy;
import hello.core.member.MemberService;
import hello.core.member.MemberServiceImpl;
import hello.core.member.MemoryMemberRepository;
import hello.core.order.OrderService;
import hello.core.order.OrderServiceImpl;

public class AppConfig {

    public MemberService memberService() {
        return new MemberServiceImpl(new MemoryMemberRepository());
    }

    public OrderService orderService() {
        return new OrderServiceImpl(new MemoryMemberRepository(), new FixDiscountPolicy());
    }

}

 

- 역할에 따른 구현이 보이지 않는다
- 중복을 제거하고, 역할에 따른 구현이 보이도록 리팩터링 하자.

"리팩터링 후"

package hello.core;

import hello.core.discount.DiscountPolicy;
import hello.core.discount.FixDiscountPolicy;
import hello.core.member.MemberRepository;
import hello.core.member.MemberService;
import hello.core.member.MemberServiceImpl;
import hello.core.member.MemoryMemberRepository;
import hello.core.order.OrderService;
import hello.core.order.OrderServiceImpl;

public class AppConfig {

    public MemberService memberService() {
        return new MemberServiceImpl(memberRepository());
    }

    private MemberRepository memberRepository() {
        return new MemoryMemberRepository();
    }

    public OrderService orderService() {
        return new OrderServiceImpl(memberRepository(), discountPolicy());
    }

    public DiscountPolicy discountPolicy() {
        return new FixDiscountPolicy();
    }

}

- new MemoryMemberRepository() 이 부분이 중복 제거되었다. 이제 MemoryMemberRepository를 다른 구현체로
변경할 때 한 부분만 변경하면 된다.
- AppConfig를 보면 역할과 구현 클래스가 한눈에 들어온다. 애플리케이션 전체 구성이 어떻게 되어있는지 빠르게
파악할 수 있다.

 

(내 생각) 왜 public DiscountPolicy discountPolicy() { return new FixDiscountPolicy(); }

이 코드에 관련된 에러가 2개나 나오는 것인지 알아봐야되겠다.

- error 2개 모두 같은 코드상에서 발생하고 있다. (OrderApp.java와 OrderServiceTest.java)

MemberService memberService = new MemberServiceImpl();