public interface OAuthMember {
    String id();
    String email();
    String nickname();
    String imageUrl();
}

public enum Provider {

    GOOGLE("google", GoogleMember::new),
    ;

    private final String providerName;
    private final Function<Map<String, Object>, OAuthMember> function;

    Provider(String providerName, Function<Map<String, Object>, OAuthMember> function) {
        this.providerName = providerName;
        this.function = function;
    }

    public static Provider from(String name) {
        return Arrays.stream(values())
                .filter(it -> it.providerName.equals(name))
                .findFirst()
                .orElseThrow(() -> new RuntimeExceptin());
    }

    public OAuthMember getOAuthProvider(Map<String, Object> body) {
        return function.apply(body);
    }
}

        @Value("oauth.provider.google.id")
        private String id;
        @Value("oauth.provider.google.secret")
        private String secret;

        ...

@Component
@ConfigurationProperties(prefix = "oauth2")
public class OAuthProviderProperties {
    // prefix oauth2 기준으로 알아서 google이 이름인 Provider Enum을 찾아서 Key로 바인딩
    private final Map<Provider, OAuthProviderProperty> provider = new EnumMap<>(Provider.class);

    public OAuthProviderProperty getProviderProperties(Provider provider) {
        return this.provider.get(provider);
    }

    @Getter
    @Setter
    public static class OAuthProviderProperty {
        // 그리고 provider 하위 정보들은 아래의 필드에 바인딩
        private String id;
        private String secret;
        private String redirectUrl;
        private String tokenUrl;
        private String infoUrl;
    }
}

public class RestTemplateOAuthRequester implements OAuthRequester {

    @Override
    public OAuthMember login(OAuthLoginRequest request) {
        // frontend에서 받아온 로그인 platform
        Provider provider = Provider.from(request.provider());
        // 해당 Platform에 맞는 정보 찾음
        OAuthProviderProperty property = oAuthProviderProperties.getProviderProperties(provider);
        // frontend에서 받아온 code와 등록해놓은 property로 Access Token 요청
        OAuthTokenResponse token = requestAccessToken(property, requet.getCode());
        // 받아온 Token으로 해당 Resource Owner의 정보 요청
        Map<String, Object> userAttributes = getUserAttributes(property, token);
        return provider.getOAuthProvider(userAttributes);
    }

    private OAuthTokenResponse requestAccessToken(OAuthProviderProperty property, String code) {
        HttpHeaders headers = new HttpHeaders();
        headers.setBasicAuth(property.getId(), property.getSecret());
        headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED);

        HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<>(headers);
        URI tokenUri = getTokenUri(property, code);
        return restTemplate.postForEntity(tokenUri, request, OAuthTokenResponse.class).getBody();
    }

    private URI getTokenUri(OAuthProviderProperty property, String code) {
        return UriComponentsBuilder.fromUriString(property.getTokenUrl())
                .queryParam(CODE, URLDecoder.decode(code, StandardCharsets.UTF_8))
                .queryParam(GRANT_TYPE, AUTHORIZATION_CODE)
                .queryParam(REDIRECT_URI, property.getRedirectUrl())
                .build()
                .toUri();
    }

    private Map<String, Object> getUserAttributes(OAuthProviderProperty property, OAuthTokenResponse tokenResponse) {
        HttpHeaders headers = new HttpHeaders();
        headers.setBearerAuth(tokenResponse.accessToken());
        headers.setContentType(MediaType.APPLICATION_JSON);
        URI uri = URI.create(property.getInfoUrl());
        RequestEntity<?> requestEntity = new RequestEntity<>(headers, HttpMethod.GET, uri);
        ResponseEntity<Map<String, Object>> responseEntity = restTemplate.exchange(requestEntity, new ParameterizedTypeReference<>() {
        });
        return responseEntity.getBody();
    }
}