public class PracticeDemo1 {
    public static void main(String[] args) throws IOException {
        BufferedInputStream bis = new BufferedInputStream(new FileInputStream("E:\\space saving.PNG"));
        byte[] bys = new byte[13];
//        int len = bis.read(bys);
        int len;
//        int i=0;
        while((len=bis.read(bys))!=-1){
            System.out.println(test(bys));
//            i++;
//            if(i==10){
//                break;
//            }
        }
//        System.out.println(test(bys));
        bis.close();
    }
    public static String test(byte[]bys){
        String str2 = "";
        StringBuffer stringBuffer=new StringBuffer();
        for (int i = 0; i < bys.length; i++) {
            String str = Integer.toHexString((int) bys[i]);
            String str1="";
            if (bys[i] < 0&&str.length()>=2) {
                str1 = str.substring(str.length() - 2);
            }
            if (i != bys.length - 1) {
                if (bys[i] < 0) {
                    stringBuffer.append(str1).append(",");
                } else {
                    stringBuffer.append(str).append(",");
                }
            } else {
                if (bys[i] < 0) {
                    stringBuffer.append(str1);
                } else {
                    stringBuffer.append(str);
                }
            }
        }
        return stringBuffer.toString();
    }
}