java缓冲流复制文件

• 字节缓冲

　　public static void main(String[] args) throws IOException {
        long start = System.currentTimeMillis();
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream("src\1.jpg"));
        BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("src\1_copy.jpg"));
        int len=0;
        byte[] bytes = new byte[1024];
        while((len =bis.read(bytes))!=-1){
            bos.write(bytes,0,len);
        }
        bos.close();
        bis.close();

        long end = System.currentTimeMillis();
        System.out.println("共耗时："+(end-start)+"s");
    }

• 字符缓冲

　　对于中文，一个字符由于编码不同可能等于两个字节，也有可能等于三个字节。字符流解决了中文转换的乱码问题。

        long start = System.currentTimeMillis();
        BufferedReader br = new BufferedReader(new FileReader("src\buffer2.txt"));
        BufferedWriter bw = new BufferedWriter(new FileWriter("src\buffer2_copy.txt"));
        String line ;
        while((line=br.readLine())!=null){
            System.out.println(line);
            bw.write(line);
            bw.newLine();
        }
        bw.flush();
        bw.close();
        br.close();
        long end = System.currentTimeMillis();
        System.out.println("共耗时："+(end-start)+"s");
    }