문자열 변환(String Charset), UTF-8 <=> EUC-KR (인코딩)

https://www.dukgun.com/2021/03/java-string-string-getbytes.html?m=1

[JAVA] String 문자열 인코딩 방법 - String getBytes()

https://whitekeyboard.tistory.com/573

[Java - (17) ] String 문자열 원하는 인코딩으로 변환하기

https://dev.re.kr/m/87

스트링 엔코딩 변환 - euc-kr <---> utf-8

- java file save euc-kr to utf-8
https://infondgndg91.blogspot.com/2018/12/java-euc-kr-text-file-convert-to-utf-8.html

Java EUC-KR text File Convert to UTF-8 text File

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;

public class Convert {

    public static void main(String[] args) throws IOException {
        String path = Convert.class.getResource("").getPath();

        BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(path + "개인가계부.txt"), "EUC-KR"));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream("utf8.txt"), "utf-8"));
        String line;
        while ((line = br.readLine()) != null) {
        //System.out.println(line);
        String utf8 = new String(line.getBytes(),"UTF-8");
        System.out.println(utf8);
        bw.write(utf8);
        bw.newLine();
        }
        bw.flush();
        br.close();
        bw.close();
        System.out.println("Done!");
    }
}