java io - copyFile

package io;

import java.io.*;

/**
 * Created by Wangjianxin on 2017/8/24 0024.
 */
public class copyFile {


    public static void main(String[] args) {
        try {
            coptbybuff();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static void copy() throws IOException{

        String src = "C:\\Users\\Administrator\\Desktop\\filetest\\wangjianxin.txt";
        String tag = "C:\\Users\\Administrator\\Desktop\\filetest\\newwangjianxin.txt";

        File file = new File(src);
        File file2 = new File(tag);
        if(!file.exists())
            throw new IllegalArgumentException("不存在");

        FileInputStream in = new FileInputStream(file);

        FileOutputStream out = new FileOutputStream(file2);

        byte[] buff = new byte[8*1024];

        int b = 1;

        while ((b=in.read(buff,0,buff.length)) != -1){
            out.write(buff,0,b);
        }

        in.close();
        out.close();

    }

    public static void coptbybuff() throws IOException{

        String src = "C:\\Users\\Administrator\\Desktop\\filetest\\wangjianxin.txt";
        String tag = "C:\\Users\\Administrator\\Desktop\\filetest\\buffwangjianxin.txt";

        File file = new File(src);
        File file2 = new File(tag);

        BufferedInputStream bis = new BufferedInputStream(new FileInputStream(file));

        BufferedOutputStream ois = new BufferedOutputStream(new FileOutputStream(file2));

        int c = 1;

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

            ois.write(c);
            ois.flush();

        }

        bis.close();
        ois.close();


    }
}