public class CopyDemo {
    public static void main(String[] args) throws Exception{
        long time1 = System.currentTimeMillis();
        copy4(new File("d:\\ccc.mp4"),new File("e:\\ccc.mp4"));
        long time2 = System.currentTimeMillis();
        System.out.println(time2-time1);
    }
    //1.字節流讀寫單個字節   太慢了
 

    public static void copy1(File src,File desc) throws Exception{
        FileInputStream fis = new FileInputStream(src);
        FileOutputStream fos = new FileOutputStream(desc);
        int len = 0;
        while ((len=fis.read())!=-1){
            fos.write(len);
        }
        fos.close();
        fis.close();
 

    }
    //2.字節流讀寫字節數組   550
    public static void copy2(File src,File desc) throws Exception{
        FileInputStream fis = new FileInputStream(src);
        FileOutputStream fos = new FileOutputStream(desc);
        int len = 0;
        byte[] b = new byte[1024*10];
        while ((len=fis.read(b))!=-1){
            fos.write(b,0,len);
 

        }
        fos.close();
        fis.close();
    }
    //3.字節流緩沖區  讀寫單個字節   4252
    public static void copy3(File src,File desc) throws Exception{
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream(src));
        BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(desc));
        int len = 0;
        while ((len=bis.read())!=-1){
            bos.write(len);
        }
        bis.close();
        bos.close();
    }
    //4.字節流緩沖區讀寫字節數組   585
    public static void copy4(File src,File desc) throws  Exception{
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream(src));
        BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(desc));
        int len = 0;
        byte[] b = new byte[1024*10];
        while ((len=bis.read(b))!=-1){
            bos.write(b,0,len);
        }
        bos.close();
        bis.close();
    }

JAVA之用緩沖流讀寫文件