LocalDateTime format 변경하는법

import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;

public class Main {
    public static void main(String[] args) {
        LocalDateTime dateTime = LocalDateTime.now();
        
        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
        String formattedDateTime = dateTime.format(formatter);
        
        System.out.println(formattedDateTime);
    }
}

내코드에는 아래처럼 적용

private List<Object> TupleToList(List<Tuple> fetch) {
        QBoard board = QBoard.board;
        QReply reply = QReply.reply;

        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");


        List<Object> list = new ArrayList<Object>();
        list.add(BoardDTO.builder()
                .bno(fetch.get(0).get(board).getBno())
                .title(fetch.get(0).get(board).getTitle())
                .content(fetch.get(0).get(board).getContent())
                .writer(fetch.get(0).get(board).getWriter().getNickname())
                .replyCount(fetch.size())
                .regDate(fetch.get(0).get(board).getRegDate().format(formatter))
                .modDate(fetch.get(0).get(board).getModDate().format(formatter))
                .build()
        );
        for (int i = 0; i < fetch.size(); i++) {
            list.add(ReplyDTO.builder()
                    .rno(fetch.get(i).get(reply).getRno())
                    .content(fetch.get(i).get(reply).getContent())
                    .replyer(fetch.get(i).get(reply).getReplyer())
                    .writeReplyDate(fetch.get(i).get(reply).getWriteReplyDate())
                    .bno(fetch.get(i).get(reply).getBoard().getBno())
                    .build()
            );
        }

        System.out.println("list = " + list);

        return list;
    }