}

  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();
    } else if (exponent > MAX_EXPONENT) {
      return x.signum() * POSITIVE_INFINITY;
    }

    /*

  }

  /** Returns {@code true} if {@code x} represents a power of two. */
  public static boolean isPowerOfTwo(BigInteger x) {
    checkNotNull(x);
    return x.signum() > 0 && x.getLowestSetBit() == x.bitLength() - 1;
  }

  /**
   * Returns the base-2 logarithm of {@code x}, rounded according to the specified rounding mode.
   *
   * @throws IllegalArgumentException if {@code x <= 0}

  }

  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();
    } else if (exponent > MAX_EXPONENT) {
      return x.signum() * POSITIVE_INFINITY;
    }

    /*

   */
  public static UnsignedInteger valueOf(BigInteger value) {
    checkNotNull(value);
    checkArgument(
        value.signum() >= 0 && value.bitLength() <= Integer.SIZE,
        "value (%s) is outside the range for an unsigned integer value",
        value);
    return fromIntBits(value.intValue());
  }

  /**

   */
  public static UnsignedInteger valueOf(BigInteger value) {
    checkNotNull(value);
    checkArgument(
        value.signum() >= 0 && value.bitLength() <= Integer.SIZE,
        "value (%s) is outside the range for an unsigned integer value",
        value);
    return fromIntBits(value.intValue());
  }

  /**

   */
  @CanIgnoreReturnValue
  public static UnsignedLong valueOf(BigInteger value) {
    checkNotNull(value);
    checkArgument(
        value.signum() >= 0 && value.bitLength() <= Long.SIZE,
        "value (%s) is outside the range for an unsigned long value",
        value);
    return fromLongBits(value.longValue());
  }

  /**

   */
  @CanIgnoreReturnValue
  public static UnsignedLong valueOf(BigInteger value) {
    checkNotNull(value);
    checkArgument(
        value.signum() >= 0 && value.bitLength() <= Long.SIZE,
        "value (%s) is outside the range for an unsigned long value",
        value);
    return fromLongBits(value.longValue());
  }

  /**

    // parseInt blows up on overflow as opposed to intValue() which does not.
    return Integer.parseInt(bigMean.toString());
  }

  private static boolean fitsInInt(BigInteger big) {
    return big.bitLength() <= 31;
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNullPointers() {
    NullPointerTester tester = new NullPointerTester();
    tester.setDefault(int.class, 1);

    // parseInt blows up on overflow as opposed to intValue() which does not.
    return Integer.parseInt(bigMean.toString());
  }

  private static boolean fitsInInt(BigInteger big) {
    return big.bitLength() <= 31;
  }

  @J2ktIncompatible
  @GwtIncompatible // NullPointerTester
  public void testNullPointers() {
    NullPointerTester tester = new NullPointerTester();
    tester.setDefault(int.class, 1);

    // parseInt blows up on overflow as opposed to intValue() which does not.
    return Long.parseLong(bigMean.toString());
  }

  private static boolean fitsInLong(BigInteger big) {
    return big.bitLength() <= 63;
  }

  private static final BigInteger MAX_LONG = BigInteger.valueOf(Long.MAX_VALUE);
  private static final BigInteger MIN_LONG = BigInteger.valueOf(Long.MIN_VALUE);