public String strhex() {
        String hexChar = "0123456789ABCDEF";

        StringBuilder b = new StringBuilder();
        for (int nbr = 0; nbr < data.length; nbr++) {
            int b1 = data[nbr] >>> 4 & 0xf;
            int b2 = data[nbr] & 0xf;
            b.append(hexChar.charAt(b1));
            b.append(hexChar.charAt(b2));
        }
        return b.toString();
    }