@IgnoreJRERequirement
  public static <T extends @Nullable Object> Supplier<T> memoizeWithExpiration(
      Supplier<T> delegate, Duration duration) {
    checkNotNull(delegate);
    // The alternative of `duration.compareTo(Duration.ZERO) > 0` causes J2ObjC trouble.
    checkArgument(
        !duration.isNegative() && !duration.isZero(), "duration (%s) must be > 0", duration);

  private static final BigInteger MIN_INT = BigInteger.valueOf(Integer.MIN_VALUE);

  private static int saturatedCast(BigInteger big) {
    if (big.compareTo(MAX_INT) > 0) {
      return Integer.MAX_VALUE;
    }
    if (big.compareTo(MIN_INT) < 0) {
      return Integer.MIN_VALUE;
    }
    return big.intValue();
  }

   * to the JDK until JDK 7.
   *
   * @param a the first {@code double} to compare
   * @param b the second {@code double} to compare
   * @return a negative value if {@code a} is less than {@code b}; a positive value if {@code a} is
   *     greater than {@code b}; or zero if they are equal
   */
  @InlineMe(replacement = "Double.compare(a, b)")
  public static int compare(double a, double b) {

        return new ExceptionSummary(null, message, null, children);
    }

    private ExceptionSummary handle(ModelProblem problem, String projectId) {
        if (ModelProblem.Severity.ERROR.compareTo(problem.getSeverity()) >= 0) {
            String message = problem.getMessage();

            String location = ModelProblemUtils.formatLocation(problem, projectId);

            if (!location.isEmpty()) {

            this.version = version;
            this.repository = repository;
        }

        boolean isOutdated(String timestamp) {
            return timestamp != null && timestamp.compareTo(this.timestamp) > 0;
        }
    }

    private static class Key {

        private final String groupId;

        private final String artifactId;

        private final String classifier;

    return new NullFriendlyComparator<>();
  }

  private static final class NullFriendlyComparator<T> implements Comparator<T>, Serializable {
    @Override
    public int compare(T left, T right) {
      return String.valueOf(left).compareTo(String.valueOf(right));
    }
  }

   * @param b the second {@code boolean} to compare
   * @return a positive number if only {@code a} is {@code true}, a negative number if only {@code
   *     b} is true, or zero if {@code a == b}
   */
  @InlineMe(replacement = "Boolean.compare(a, b)")
  public static int compare(boolean a, boolean b) {
    return Boolean.compare(a, b);
  }

  /**

   * @param b the second {@code boolean} to compare
   * @return a positive number if only {@code a} is {@code true}, a negative number if only {@code
   *     b} is true, or zero if {@code a == b}
   */
  @InlineMe(replacement = "Boolean.compare(a, b)")
  public static int compare(boolean a, boolean b) {
    return Boolean.compare(a, b);
  }

  /**

  }

  public void testCustomComparator() throws Exception {
    Comparator<String> comparator =
        new Comparator<String>() {
          @Override
          public int compare(String o1, String o2) {
            return o2.compareTo(o1);
          }
        };
    TreeMultiset<String> ms = TreeMultiset.create(comparator);

    ms.add("b");
    ms.add("c");
    ms.add("a");
    ms.add("b");

  }

  private static class IntegerDiv10 implements Comparable<IntegerDiv10> {
    final int value;

    IntegerDiv10(int value) {
      this.value = value;
    }

    @Override
    public int compareTo(IntegerDiv10 o) {
      return value / 10 - o.value / 10;
    }

    @Override
    public String toString() {
      return Integer.toString(value);
    }
  }