为什么用缓冲流读取时文本变空了？

Question

import java.io.*;public class Test3 { public static void main(String[] args) {              try{      FileReader fr=new FileReader("E:/java demo/Hello1.txt");      BufferedReader br=new BufferedReader(fr);      FileWriter fw=new FileWriter("E:/java demo/Hello1.txt");      BufferedWriter bw=new BufferedWriter(fw);      String s;            s=br.readLine();      System.out.println(s);           fr.close();      br.close();      fw.close();      bw.close();       }       catch(IOException ioe){System.out.println(ioe);} }}

Answer 1

FileReader fr=new FileReader("E:/java demo/Hello1.txt");

FileWriter fw=new FileWriter("E:/java demo/Hello1.txt");

Answer 2

  FileReader fr=new FileReader("E:/java demo/Hello1.txt");

FileWriter fw=new FileWriter("E:/java demo/Hello1.txt");