字节缓冲流 BufferedOutputStream BufferedInputStream

Posted 2021-11-09 qurui1998

/*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();
    }

}