자바 txt file 읽어와서 map에 저장 후 출력시 오류(인코딩) 질문드립니다..

import java.io.*;
import java.util.Scanner;
import java.util.TreeMap;
 
public class MemoMain {
    public static void main(String[] args) {
        File file = new File("C:\\Users\\Jeon\\Desktop\\user.txt");
        TreeMap<String, User> hasu = new TreeMap<>();
        String[] splitstr = null;
        Scanner scan = new Scanner(System.in);
        String num = "";
        User usr = null;
 
        try {
            FileInputStream fis = new FileInputStream(file);
            InputStreamReader isr = new InputStreamReader(fis, "UTF-8");
            BufferedReader br = new BufferedReader(isr);
 
            String buffer = "";
            while((buffer = br.readLine()) != null) {
                splitstr = buffer.split(",");
                hasu.put(splitstr0, new User(splitstr1, splitstr2, splitstr3));
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
 
        while(true) {
            usr = new User();
            System.out.println("검색하실 사용자 번호를 입력하세요");
            num = scan.nextLine();
            System.out.println(hasu.descendingKeySet());
            System.out.println(hasu.entrySet());
 
            if (hasu.containsKey(num)) {
                usr = hasu.get(num);
                System.out.println("사용자 번호 : " + num + ", " + usr);
            } else {
                System.out.println("킷값이 존재하지 않습니다.");
            }
        }
    }
}