import java.io.*;
import java.util.*;


public class Replace {
    public static void main(String[] args) {
        File res=new File("D:\\App\\Eclipse IDE\\Matrix\\src\\core\\New.java");
        File st=new File("D:\\App\\Eclipse IDE\\Matrix\\src\\core\\Matrix.java");
        String s="";
        try {
            FileReader fr = new FileReader(st);
            FileWriter fw = new FileWriter(res);
            Scanner scan=new Scanner(fr);
            while(scan.hasNext()){
                s=scan.nextLine();
                s.replace("public", "private");
                    fw.append(s);
                    fw.flush();
            }
            fr.close();
            fw.close();
            scan.close();
            } catch (IOException e) {
            System.err.println("ошибка файла: " + e);
            }
    }

}