Kakaopay클래스오류가 납니다

카카오페이 API
#1

package kr.or.ddit.pay.service;

import java.net.URI;
import java.net.URISyntaxException;

import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Service;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.web.client.RestClientException;
import org.springframework.web.client.RestTemplate;

import kr.or.ddit.vo.GradeVO;
import kr.or.ddit.vo.KaKaoPayApprovalVO;
import kr.or.ddit.vo.KakaoPayReadyVO;
import kr.or.ddit.vo.PaymentVO;
import lombok.extern.java.Log;

@Service
@Log
public class KakaoPay {
private static final String HOST = “https://kapi.kakao.com”;

private KakaoPayReadyVO kakaoPayReadyVO;
private KaKaoPayApprovalVO kakaoPayApprovalVO;

public String kakaoPayReady(GradeVO grade) {

    RestTemplate restTemplate = new RestTemplate();

    // 서버로 요청할 Header
    HttpHeaders headers = new HttpHeaders();
    headers.add("Authorization", "KakaoAK " + "18a9b30eecfcbcb7a327ec00ed905c07");

// headers.add(“Accept”, MediaType.APPLICATION_JSON_UTF8_VALUE); --> 이게 안되네요ㅠ
headers.add(“Accept”, MediaType.APPLICATION_JSON_VALUE);
headers.add(“Content-Type”, MediaType.APPLICATION_FORM_URLENCODED_VALUE + “;charset=UTF-8”);

    // 서버로 요청할 Body
    MultiValueMap<String, String> params = new LinkedMultiValueMap<String, String>();
    params.add("cid", "TC0ONETIME");
    params.add("partner_order_id", grade.getGrade_no());
    params.add("partner_user_id", "쁘띠광");
    params.add("item_name", grade.getGrade_name() );
    params.add("quantity", "1");
    params.add("total_amount", grade.getGrade_price());
    params.add("tax_free_amount", "100");
    params.add("approval_url", "http://localhost/pay/kakaoPaySuccess?grade_no="+grade.getGrade_no());
    params.add("cancel_url", "http://localhost/pay/kakaoPayCancel");
    params.add("fail_url", "http://localhost/pay/kakaoPaySuccessFail");

    HttpEntity<MultiValueMap<String, String>> body = new HttpEntity<MultiValueMap<String, String>>(params, headers);

    try {
        kakaoPayReadyVO = restTemplate.postForObject(new URI(HOST + "/v1/payment/ready"), body, KakaoPayReadyVO.class);
        
        log.info("" + kakaoPayReadyVO); <--log 부분 오류 납니다 ㅠ
        
        return kakaoPayReadyVO.getNext_redirect_pc_url();

    } catch (RestClientException e) {
        e.printStackTrace();
    } catch (URISyntaxException e) {
        e.printStackTrace();
    }
    
    return "/pay";
    
}

log 부분이 안되고, headers.add(“Accept”, MediaType.APPLICATION_JSON_UTF8_VALUE); --> 이게 안되네요ㅠ
이부분 도 UTF8 때문에 오류가 납니다ㅠ 제발 도와주세요.