实现文件的复制

package io;
//实现文件的复制，文件可以包括.jpg .avi .mp2 .ppt等等
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class Copy {
    public static void main(String[] args) {
        long start=System.currentTimeMillis();
        String src="C:\\Users\\ALHH\\Desktop\\a04.jpg";
        String dest="C:\\Users\\ALHH\\Desktop\\a04.jpg";
        copyFile(src,dest);
        long end=System.currentTimeMillis();
        System.out.println(end-start);
    }

    public static void copyFile(String src,String dest){
        File file1=new File(src);
        File file2=new File(dest);

        FileInputStream fis=null;
        try {
            fis = new FileInputStream(file1);
        } catch (FileNotFoundException e) {

            e.printStackTrace();
        }
        FileOutputStream fos=null;if(fos!=null){
        try {
            fos = new FileOutputStream(file2);
        } catch (FileNotFoundException e) {

            e.printStackTrace();
        }
        byte[] b=new byte[1024];
        int len;
        try {
            while((len=fis.read())!=-1){
                fos.write(b, 0, len);
            }
        } catch (IOException e) {

            e.printStackTrace();
        }finally{
            try {
                fis.close();
            } catch (IOException e) {

                e.printStackTrace();
            }
        }}

if(fis!=null){

try { fos.close();

 } 

catch (IOException e) { e.printStackTrace(); } } }}