/*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();

    }

}