Class<?> rawType = type.getRawType();
    List<Object> samples = sampleInstances.get(rawType);
    Object sample = pickInstance(samples, null);
    if (sample != null) {
      return sample;
    }
    if (rawType.isEnum()) {
      return pickInstance(rawType.getEnumConstants(), null);
    }
    if (type.isArray()) {
      TypeToken<?> componentType = requireNonNull(type.getComponentType());

	if len(id) != 16 {
		t.Fail()
	}

	var e rune
	for _, char := range id {
		e = char

		// Ensure that it is alphanumeric, in this case, between 0-9 and A-Z.
		isAlnum := ('0' <= e && e <= '9') || ('A' <= e && e <= 'Z')
		if !isAlnum {
			t.Fail()
		}
	}

    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;
    }

    /*
     * We need the top SIGNIFICAND_BITS + 1 bits, including the "implicit" one bit. To make rounding

            new Foo("b", 1, null));
    for (Foo a : instances) {
      for (Foo b : instances) {
        int comparedUsingComparisonChain = signum(comparatorUsingComparisonChain.compare(a, b));
        int comparedUsingComparatorMethods = signum(comparatorUsingComparatorMethods.compare(a, b));
        assertWithMessage("%s vs %s", a, b)
            .that(comparedUsingComparatorMethods)

      int i = rnd.nextInt(left.length);
      left[i] ^= (byte) (1 + rnd.nextInt(255));
      assertThat(signum(comparator1.compare(left, right)))
          .isEqualTo(signum(UnsignedBytes.compare(left[i], right[i])));
      assertThat(signum(comparator2.compare(left, right)))
          .isEqualTo(signum(UnsignedBytes.compare(left[i], right[i])));
    }
  }

      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
  static int checkNonNegative(String role, int x) {
    if (x < 0) {

   */
  static BigInteger randomPositiveBigInteger(int numBits) {
    BigInteger result;
    do {
      result = randomNonNegativeBigInteger(numBits);
    } while (result.signum() == 0);
    return result;
  }

  /**
   * Generates a number in [0, 2^numBits) with an exponential distribution. The floor of the log2 of

    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;
    }

    /*
     * We need the top SIGNIFICAND_BITS + 1 bits, including the "implicit" one bit. To make rounding

    for (long a : UNSIGNED_INTS) {
      for (long b : UNSIGNED_INTS) {
        int cmpAsLongs = Long.compare(a, b);
        int cmpAsUInt = UnsignedInts.compare((int) a, (int) b);
        assertThat(Integer.signum(cmpAsUInt)).isEqualTo(Integer.signum(cmpAsLongs));
      }
    }
  }

  public void testMax_noArgs() {
    assertThrows(IllegalArgumentException.class, () -> max());
  }

  public void testMax() {

    @Override
    double roundToDoubleArbitrarily(BigDecimal bigDecimal) {
      return bigDecimal.doubleValue();
    }

    @Override
    int sign(BigDecimal bigDecimal) {
      return bigDecimal.signum();
    }

    @Override
    BigDecimal toX(double d, RoundingMode mode) {
      return new BigDecimal(d);
    }

    @Override
    BigDecimal minus(BigDecimal a, BigDecimal b) {
      return a.subtract(b);