}

  static class DurationSpec {
    private final long duration;
    private final TimeUnit unit;

    private DurationSpec(long duration, TimeUnit unit) {
      this.duration = duration;
      this.unit = unit;
    }

    public static DurationSpec of(long duration, TimeUnit unit) {
      return new DurationSpec(duration, unit);
    }

    @Override
    public int hashCode() {

    }
  }

  @GwtIncompatible // java.time.Duration
  public void testTimeToLive_setTwice_duration() {
    CacheBuilder<Object, Object> builder =
        CacheBuilder.newBuilder().expireAfterWrite(java.time.Duration.ofSeconds(3600));
    assertThrows(
        IllegalStateException.class,
        () -> builder.expireAfterWrite(java.time.Duration.ofSeconds(3600)));
  }

  public void testTimeToIdle_negative() {

 *   <li>{@code maximumWeight=[long]}: sets {@link CacheBuilder#maximumWeight}.
 *   <li>{@code expireAfterAccess=[duration]}: sets {@link CacheBuilder#expireAfterAccess}.
 *   <li>{@code expireAfterWrite=[duration]}: sets {@link CacheBuilder#expireAfterWrite}.
 *   <li>{@code refreshAfterWrite=[duration]}: sets {@link CacheBuilder#refreshAfterWrite}.
 *   <li>{@code weakKeys}: sets {@link CacheBuilder#weakKeys}.

    assertEquals(6000000000L, ticker.read());
  }

  @GwtIncompatible // java.time.Duration
  @SuppressWarnings("Java7ApiChecker") // guava-android can rely on library desugaring now.
  public void testAutoIncrementStep_duration() {
    FakeTicker ticker = new FakeTicker().setAutoIncrementStep(Duration.ofMillis(1));
    assertEquals(0, ticker.read());
    assertEquals(1000000, ticker.read());

    }
  }

  @SuppressWarnings("Java7ApiChecker") // test of Java 8+ API
  @J2ktIncompatible // Duration
  @GwtIncompatible // Duration
  public void testMemoizeWithExpiration_durationNegative() throws InterruptedException {
    try {
      Supplier<String> unused = Suppliers.memoizeWithExpiration(() -> "", Duration.ZERO);
      fail();
    } catch (IllegalArgumentException expected) {
    }

    try {

    }
  }

  @SuppressWarnings("Java7ApiChecker") // test of Java 8+ API
  @J2ktIncompatible // Duration
  @GwtIncompatible // Duration
  public void testMemoizeWithExpiration_durationNegative() throws InterruptedException {
    try {
      Supplier<String> unused = Suppliers.memoizeWithExpiration(() -> "", Duration.ZERO);
      fail();
    } catch (IllegalArgumentException expected) {
    }

    try {

  }

  static class DurationSpec {
    private final long duration;
    private final TimeUnit unit;

    private DurationSpec(long duration, TimeUnit unit) {
      this.duration = duration;
      this.unit = unit;
    }

    public static DurationSpec of(long duration, TimeUnit unit) {
      return new DurationSpec(duration, unit);
    }

    @Override
    public int hashCode() {

  @GwtIncompatible // java.time.Duration
  @SuppressWarnings("Java7ApiChecker") // no more dangerous that wherever the user got the Duration
  @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(

   * uninterruptibly.
   */
  @J2ktIncompatible
  @GwtIncompatible // concurrency
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
  public static boolean awaitUninterruptibly(CountDownLatch latch, long timeout, TimeUnit unit) {
    boolean interrupted = false;
    try {
      long remainingNanos = unit.toNanos(timeout);

  public FakeTicker advance(Duration duration) {
    return advance(duration.toNanos());
  }

  /**
   * Sets the increment applied to the ticker whenever it is queried.
   *
   * <p>The default behavior is to auto increment by zero. i.e: The ticker is left unchanged when
   * queried.
   */
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
  @CanIgnoreReturnValue