long l = ByteConversion.byteToLong(data, 3);
long l = ByteConversion.byteToLong(data, 3) ^ 0x8000000000000000L;
    public void deserialize(byte[] data) {        long l = ByteConversion.byteToLong(data, 3);        type = data[2];        value = BigInteger.valueOf(l);    }