/*缓冲流：读取数据大量的文件时，读取的速度慢java提供了一套缓冲流 提高io流的效率**/package cn.lijun.demo;import java.io.BufferedInputStream;import java.io.FileInputStream;import java.io.FileNotFoundException;/* * 字节输入流的缓冲流 * 继承InputStream * 构造方法 */public class BufferedInputStreamDemo {    public static void main(String[] args) throws Exception {        //创建字节输入流的缓冲流对象        BufferedInputStream bis=new BufferedInputStream(new FileInputStream("d:\\b.txt"));        byte[] b=new byte[1024];        int len=0;        while((len=bis.read(b))!=-1){            System.out.println(new String(b,0,len));        }        bis.close();    }}package cn.lijun.demo;import java.io.BufferedOutputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;/* * 字节输出流的缓冲流 作用  提高效率 * 继承OutputStream * 构造方法new BufferedOutputStream(OutputStream out); */public class BufferedOutputStreamDemo {    public static void main(String[] args) throws Exception {        FileOutputStream fos=new FileOutputStream("d:\\b.txt");        BufferedOutputStream bos=new BufferedOutputStream(fos);                bos.write(65);        byte[] b="hello world".getBytes();        bos.write(b);        bos.write(b,3,2);  //从索引为三的开始  截取两位数        bos.close();    }}