package demo2;

import java.io.*;

public class Stream{

    //一个字节一个字节的复制，耗时11736毫秒

    public static  void  fun() throws IOException {

        FileInputStream fis = new FileInputStream("C:\\Users\\intasect\\Desktop\\Koala.jpg");

        FileOutputStream fos = new FileOutputStream("C:\\Users\\intasect\\Desktop\\fz.jpg");

        int by = 0;

        while ((by=fis.read()) != -1) {

            fos.write(by);

        }

        fis.close();

        fos.close();

    }

    //1024字节数组复制 耗时21毫秒

    public  static void  fun1() throws IOException {

         FileInputStream fis = new FileInputStream("C:\\Users\\intasect\\Desktop\\Koala.jpg");

         FileOutputStream fos = new FileOutputStream("C:\\Users\\intasect\\Desktop\\fz.jpg");

        int len = 0;

        byte[] bytes =new byte[1024];

        while ((len=fis.read(bytes)) != -1) {

            fos.write(bytes,0,len);

        }

        fis.close();

        fos.close();

    }

    // 一个字节一个字节复制，但是用了缓冲流 耗时64毫秒

    public static   void  fun2() throws IOException {

        BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("C:\\Users\\intasect\\Desktop\\fz.jpg"));

        BufferedInputStream bis = new BufferedInputStream(new FileInputStream("C:\\Users\\intasect\\Desktop\\Koala.jpg"));

        int by = 0;

        while ((by=bis.read()) != -1) {

            bos.write(by);

        }

        bis.close();

        bos.close();

    }

    // 1024字节数组复制并用了缓冲流 耗时7毫秒

    public  static void  fun3() throws IOException {

        BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("C:\\Users\\intasect\\Desktop\\fz.jpg"));

        BufferedInputStream bis = new BufferedInputStream(new FileInputStream("C:\\Users\\intasect\\Desktop\\Koala.jpg"));

        int len = 0;

        byte[] bytes =new byte[1024];

        while ((len=bis.read(bytes)) != -1) {

            bos.write(bytes,0,len);

        }

        bis.close();

        bos.close();

    }

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

        long t1 = System.currentTimeMillis();

        fun3();

        long t2 = System.currentTimeMillis();

        System.out.println(t2-t1);

    }

}