이너 static class

package hello.core.beanfind;

import hello.core.AppConfig;
import hello.core.repository.MemberRepository;
import hello.core.repository.MemoryMemberRepository;
import hello.core.service.MemberService;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
import org.springframework.beans.factory.UnsatisfiedDependencyException;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import static org.junit.jupiter.api.Assertions.*;

public class ApplicationContextSameBeanFindTest {
    AnnotationConfigApplicationContext ac=new AnnotationConfigApplicationContext(SameBeanConfig.class);

    @Test
    @DisplayName("타입으로 조회시 같은 타입이 둘 이상 있으면, 중복 오류가 발생한다")
    void findBeanByTypeDuplicate() {
        //DiscountPolicy bean = ac.getBean(MemberRepository.class);
        assertThrows(NoUniqueBeanDefinitionException.class, () ->
                ac.getBean(MemberRepository.class));
    }

        @Configuration
        static class SameBeanConfig{

        @Bean
        public MemberRepository memberRepository(){
            return new MemoryMemberRepository();
        }
        @Bean
        public MemberRepository memberRepository2(){
            return new MemoryMemberRepository();
        }
    }
이 코드에서 static이너클래스면 실행이 되고 그냥 이너클래스이면 안되는 이유가 뭔지
궁금합니다.



}