org.springframework.beans.factory.UnsatisfiedDependencyException

[질문 템플릿]
1. 강의 내용과 관련된 질문인가요? (예/아니오) 예
2. 인프런의 질문 게시판과 자주 하는 질문에 없는 내용인가요? (예/아니오) 예
3. 질문 잘하기 메뉴얼을 읽어보셨나요? (예/아니오) 예

[질문 내용]
section7 @Autowired 필드 명, @Qualifier, @Primary의 약 2:16초

강의의 내용대로 아래의 코드를

public OrderServiceImpl(MemberRepository memberRepository, DiscountPolicy discountPolicy)

@Autowired
public OrderServiceImpl(MemberRepository memberRepository, DiscountPolicy rateDiscountPolicy) {
    this.memberRepository = memberRepository;
    this.discountPolicy = rateDiscountPolicy;
}

이렇게 바꿔주었지만

AutoAppConfigTest > basicScan()에서

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'orderServiceImpl' defined in file [/Users/dani/Desktop/dani/practice-spring/spring-basic/core/out/production/classes/hello/core/order/OrderServiceImpl.class]: Unsatisfied dependency expressed through constructor parameter 1: No qualifying bean of type 'hello.core.discount.DiscountPolicy' available: expected single matching bean but found 2: fixDiscountPolicy,rateDiscountPolicy

at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:798)

at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:237)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1354)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1191)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:561)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:521)

at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:325)

at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)

at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:323)

at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)

at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:975)

at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:959)

at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:624)

at org.springframework.context.annotation.AnnotationConfigApplicationContext.<init>(AnnotationConfigApplicationContext.java:93)

at hello.core.scan.AutoAppConfigTest.basicScan(AutoAppConfigTest.java:16)

at java.base/java.lang.reflect.Method.invoke(Method.java:580)

at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)

at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)

Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'hello.core.discount.DiscountPolicy' available: expected single matching bean but found 2: fixDiscountPolicy,rateDiscountPolicy

at org.springframework.beans.factory.config.DependencyDescriptor.resolveNotUnique(DependencyDescriptor.java:218)

at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1420)

at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1353)

at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:907)

at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:785)

... 17 more

오류가 났습니다.

그래서 https://docs.google.com/document/d/1j0jcJ9EoXMGzwAA2H0b9TOvRtpwlxI5Dtn3sRtuXQas/edit#heading=h.b1yk4ued1pxo

이 문서의 해결방안3대로 해보았더니

BeanDefinitionTest > 빈 설정 메타정보 확인

XmlAppContext > xmlAppContext()에서

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'orderService' defined in class path resource [appConfig.xml]: Unsatisfied dependency expressed through constructor parameter 1: Ambiguous argument values for parameter of type [hello.core.discount.DiscountPolicy] - did you specify the correct bean references as arguments?

at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:779)

at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:237)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1354)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1191)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:561)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:521)

at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:325)

at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)

at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:323)

at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)

at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:975)

at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:959)

at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:624)

at org.springframework.context.support.GenericXmlApplicationContext.<init>(GenericXmlApplicationContext.java:71)

at hello.core.beandefinition.BeanDefinitionTest.<init>(BeanDefinitionTest.java:13)

at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:502)

at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:486)

at java.base/java.util.Optional.orElseGet(Optional.java:364)

at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)

at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)

같은 오류가 발생하였습니다.

어떻게 해결하면 될까요?

아래는 저의 코드입니다.

package hello.core;
import hello.core.discount.DiscountPolicy;
import hello.core.discount.FixDiscountPolicy;
import hello.core.discount.RateDiscountPolicy;
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;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
public class AppConfig {

    @Bean
    public MemberService memberService() {
        System.out.println("call AppConfig.memberService");
        return new MemberServiceImpl(memberRepository());
    }
    @Bean
    public MemberRepository memberRepository() {
        System.out.println("call AppConfig.memberRepository");
        return new MemoryMemberRepository();
    }
    @Bean
    public OrderService orderService() {
        System.out.println("call AppConfig.orderService");
        return new OrderServiceImpl(memberRepository(), discountPolicy());
//        return null;
    }
    @Bean
    public DiscountPolicy discountPolicy() {
        return new RateDiscountPolicy();
    }
}

package hello.core.order;

import hello.core.discount.DiscountPolicy;
import hello.core.discount.FixDiscountPolicy;
import hello.core.discount.RateDiscountPolicy;
import hello.core.member.Member;
import hello.core.member.MemberRepository;
import hello.core.member.MemoryMemberRepository;
import lombok.RequiredArgsConstructor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Component
//@RequiredArgsConstructor //생성자 만들어줌
public class OrderServiceImpl implements OrderService {
    private final MemberRepository memberRepository;
    private final DiscountPolicy discountPolicy; //추상화인 인터페이스에 의존

    @Autowired
    public OrderServiceImpl(MemberRepository memberRepository, DiscountPolicy rateDiscountPolicy) {
        this.memberRepository = memberRepository;
        this.discountPolicy = rateDiscountPolicy;
    }

    @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);
    }

    //테스트 용도
    public MemberRepository getMemberRepository() {
        return memberRepository;
    }
}

+) 방법2도 추가로 실행해보았으나 같은 결과가 떴습니다.

@Autowired
public OrderServiceImpl(MemberRepository memberRepository, DiscountPolicy discountPolicy) {
    this.memberRepository = memberRepository;
    this.discountPolicy = discountPolicy;
}

@Autowired
public OrderServiceImpl(MemberRepository memberRepository, DiscountPolicy rateDiscountPolicy) {
    this.memberRepository = memberRepository;
    this.discountPolicy = rateDiscountPolicy;
}