java如何读写txt文件

package readAndWrite;
import java.io.*;
public class TXT {
public static void main(String[] args) throws IOException
{
String readSource = "F:\\ReadTXT.txt";
FileInputStream fis = new FileInputStream(readSource);
InputStreamReader isr = new InputStreamReader(fis);
BufferedReader  br =  new BufferedReader(isr);
String writeDest = "F:\\WriteTXT.txt";
File file = new File(writeDest);
FileWriter fw = new FileWriter(file);
BufferedWriter bw = new BufferedWriter(fw);
String line;
for(;(line=br.readLine())!=null;){
bw.write(line);
bw.write("\r\n");
}
bw.close();
fw.close();
br.close();
isr.close();
fis.close();
}
}