Java中复制文件和文件夹的操作，异常未处理，无注释-_-!

import java.io.*;

class CopyDir

{

public static void main(String[] args)throws IOException

{

File sour=new File("F://java//java.txt");

File des=new File("F://1234");

copyDir(sour,des);

}

public static void copyDir(File sour,File de)throws IOException

{

if(sour.isFile())

{

File fs=new File(de,sour.getName());

copyFile(sour,fs);

}

else

{

File des=new File(de,sour.getName());

des.mkdir();

File[] arr=sour.listFiles();

for(File f:arr)

{

if(f.isFile())

{

File fs=new File(des,f.getName());

fs.createNewFile();

copyFile(f,fs);

}

else

{

File fs=new File(des,f.getName());

fs.mkdir();

copyDir(f,fs);

}

}

}

}

public static void copyFile(File f1,File f2)throws IOException

{

BufferedInputStream bis=new BufferedInputStream(new FileInputStream(f1));

BufferedOutputStream bos=new BufferedOutputStream(new FileOutputStream(f2));

for(int num;(num=bis.read())!=-1;)

{

bos.write(num);

}

bos.close();

bis.close();

}

}