字节缓冲区读写文件

import java.io.*;

public class Demo04
{
    public static void main(String s[]) throws Exception
    {
        InputStream          is  = new FileInputStream("Demo04.java");
        BufferedInputStream  bis = new BufferedInputStream(is);
        
        OutputStream         os  = new FileOutputStream("Demo03.txt");
        BufferedOutputStream bos = new BufferedOutputStream(os);
        
        byte data[] = new byte[50];//设置缓冲区大小
        int id;//可以省略
        while((id=bis.read(data))!=-1)//判断是否读到末尾
        {
            bos.write(data);
            String str = new String(data);
            System.out.print(str);
            Thread.sleep(2000); 
        }
        bis.close();bos.close();
        is.close();os.close();
    }   
}