if (x <= 0) {
      throw new IllegalArgumentException(role + " (" + x + ") must be > 0");
    }
    return x;
  }

  @CanIgnoreReturnValue
  static BigInteger checkPositive(String role, BigInteger x) {
    if (x.signum() <= 0) {
      throw new IllegalArgumentException(role + " (" + x + ") must be > 0");
    }
    return x;
  }

  @CanIgnoreReturnValue

   * Returns the {@code Inet4Address} corresponding to a given {@code BigInteger}.
   *
   * @param address BigInteger representing the IPv4 address
   * @return Inet4Address representation of the given BigInteger
   * @throws IllegalArgumentException if the BigInteger is not between 0 and 2^32-1
   * @since 28.2
   */
  public static Inet4Address fromIPv4BigInteger(BigInteger address) {

    long significand = doubleToRawLongBits(x) & SIGNIFICAND_MASK;
    return longBitsToDouble(significand | ONE_BITS);
  }

  static double bigToDouble(BigInteger x) {
    // This is an extremely fast implementation of BigInteger.doubleValue(). JDK patch pending.
    BigInteger absX = x.abs();
    int exponent = absX.bitLength() - 1;
    // exponent == floor(log2(abs(x)))
    if (exponent < Long.SIZE - 1) {
      return x.longValue();

    public void testReadFiletime() throws IOException {
        // A non-null date
        long time = System.currentTimeMillis();
        BigInteger filetime = BigInteger.valueOf(time)
                .add(BigInteger.valueOf(SmbConstants.MILLISECONDS_BETWEEN_1970_AND_1601))
                .multiply(BigInteger.valueOf(10000L));

        byte[] data = new byte[8];
        long low = filetime.longValue();

      BigInteger.valueOf(Integer.MAX_VALUE)
          .multiply(BigInteger.valueOf(3L))
          .divide(BigInteger.valueOf(4L))
          .doubleValue();
  static final double LARGE_INTEGER_VALUES_POPULATION_VARIANCE =
      BigInteger.valueOf(Integer.MAX_VALUE)
          .multiply(BigInteger.valueOf(Integer.MAX_VALUE))
          .divide(BigInteger.valueOf(16L))
          .doubleValue();

    }

    @Test
    void testConstructorWithBigIntegerVersion() throws IOException {
        // Test with a BigInteger Kerberos version
        byte[] validToken = createTestTicketBytes(new BigInteger(KerberosConstants.KERBEROS_VERSION), SERVER_REALM, SERVER_PRINCIPAL_NAME,
                ENCRYPTION_TYPE, ENCRYPTED_DATA, null);

    return (double) ((value >>> 1) | (value & 1)) * 2.0;
  }

  /** Returns the value of this {@code UnsignedLong} as a {@link BigInteger}. */
  public BigInteger bigIntegerValue() {
    BigInteger bigInt = BigInteger.valueOf(value & UNSIGNED_MASK);
    if (value < 0) {
      bigInt = bigInt.setBit(Long.SIZE - 1);
    }
    return bigInt;
  }

  @Override

                if (!pvno.getValue().equals(new BigInteger(KerberosConstants.KERBEROS_VERSION))) {
                    throw new PACDecodingException("Invalid kerberos version");
                }
                break;
            case 1:
                ASN1Integer msgType = ASN1Util.as(ASN1Integer.class, tagged);
                if (!msgType.getValue().equals(new BigInteger(KerberosConstants.KERBEROS_AP_REQ))) {

   */
  @Override
  public double doubleValue() {
    return longValue();
  }

  /** Returns the value of this {@code UnsignedInteger} as a {@link BigInteger}. */
  public BigInteger bigIntegerValue() {
    return BigInteger.valueOf(longValue());
  }

  /**
   * Compares this unsigned integer to another unsigned integer. Returns {@code 0} if they are

    long significand = doubleToRawLongBits(x) & SIGNIFICAND_MASK;
    return longBitsToDouble(significand | ONE_BITS);
  }

  static double bigToDouble(BigInteger x) {
    // This is an extremely fast implementation of BigInteger.doubleValue(). JDK patch pending.
    BigInteger absX = x.abs();
    int exponent = absX.bitLength() - 1;
    // exponent == floor(log2(abs(x)))
    if (exponent < Long.SIZE - 1) {
      return x.longValue();