JAVA

SettingsActivity.java

private String getHexCounter(int i) {
        String hex = Integer.toHexString(i);
        switch (hex.length()) {
            case 1:
                return '0' + hex + " 00";
            case 2:
                return hex + " 00";
            case 3:
                return hex.substring(1) + " 0" + hex.charAt(0);
            case 4:
                return hex.substring(2) + ' ' + hex.substring(0, 2);
            default:
                return "ololo";
        }
    }

    private String toHexString(byte[] array, int limit) {

        char[] HEX_CHARS = "0123456789ABCDEF".toCharArray();

        StringBuffer result = new StringBuffer();

        if (array.length == 0) {
            return "";
        }

        for (int i = 0; i < array.length; ++i) {
            if (i == limit) {
                break;
            }
            int octet = array[i];
            int firstIndex = (octet & 0xF0) >>> 4;
            int secondIndex = octet & 0x0F;
            result.append(HEX_CHARS[firstIndex]);
            result.append(HEX_CHARS[secondIndex]);
            result.append(' ');
        }


        String res = result.toString();
        return res.substring(0, res.length() - 1);
    }