* two.)
   *
   * @throws ArithmeticException if {@code mode} is {@link RoundingMode#UNNECESSARY} and {@code x}
   *     is not precisely representable as a {@code double}
   * @since 30.0
   */
  public static double roundToDouble(BigDecimal x, RoundingMode mode) {
    return BigDecimalToDoubleRounder.INSTANCE.roundToDouble(x, mode);
  }

  private static final class BigDecimalToDoubleRounder extends ToDoubleRounder<BigDecimal> {

import static java.lang.Math.nextDown;
import static java.lang.Math.nextUp;

import com.google.common.annotations.GwtIncompatible;
import java.math.RoundingMode;

/**
 * Helper type to implement rounding {@code X} to a representable {@code double} value according to
 * a {@link RoundingMode}.
 */
@GwtIncompatible
abstract class ToDoubleRounder<X extends Number & Comparable<X>> {
  /**

import com.google.caliper.Param;
import java.math.RoundingMode;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for the rounding methods of {@code LongMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class LongMathRoundingBenchmark {
  @Param({"DOWN", "UP", "FLOOR", "CEILING", "HALF_EVEN", "HALF_UP", "HALF_DOWN"})
  RoundingMode mode;

import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import java.math.BigInteger;
import java.math.RoundingMode;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for the rounding methods of {@code BigIntegerMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked

import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import java.math.BigInteger;
import java.math.RoundingMode;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for the rounding methods of {@code BigIntegerMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked

 */

package com.google.common.math;

import com.google.common.annotations.GwtCompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.math.BigInteger;
import java.math.RoundingMode;

/**
 * A collection of preconditions for math functions.
 *
 * @author Louis Wasserman
 */
@GwtCompatible
final class MathPreconditions {
  @CanIgnoreReturnValue

import static com.google.common.math.MathBenchmarking.randomPositiveDouble;

import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import java.math.RoundingMode;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for the rounding methods of {@code DoubleMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class DoubleMathRoundingBenchmark {

import com.google.caliper.Param;
import java.math.RoundingMode;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for the rounding methods of {@code LongMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class LongMathRoundingBenchmark {
  @Param({"DOWN", "UP", "FLOOR", "CEILING", "HALF_EVEN", "HALF_UP", "HALF_DOWN"})
  RoundingMode mode;

import static com.google.common.math.MathBenchmarking.randomPositiveBigInteger;

import com.google.caliper.BeforeExperiment;
import com.google.caliper.Benchmark;
import com.google.caliper.Param;
import java.math.RoundingMode;
import org.jspecify.annotations.NullUnmarked;

/**
 * Benchmarks for the rounding methods of {@code IntMath}.
 *
 * @author Louis Wasserman
 */
@NullUnmarked
public class IntMathRoundingBenchmark {

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.math.RoundingMode;
import java.util.SortedMap;
import java.util.SortedSet;
import junit.framework.TestCase;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**