*     next
     * @param unit the time unit of the initialDelay and delay parameters
     */
    @SuppressWarnings("GoodTime") // should accept a java.time.Duration
    public static Scheduler newFixedDelaySchedule(
        final long initialDelay, final long delay, final TimeUnit unit) {
      checkNotNull(unit);
      checkArgument(delay > 0, "delay must be > 0, found %s", delay);

  private static Thread acquireFor(final Lock lock, final long duration, final TimeUnit unit) {
    final CountDownLatch latch = new CountDownLatch(1);
    Thread thread =
        new Thread() {
          @Override
          public void run() {
            lock.lock();
            latch.countDown();
            try {
              Thread.sleep(unit.toMillis(duration));
            } catch (InterruptedException e) {

   * @since 23.0
   */
  @J2ktIncompatible
  @GwtIncompatible // java.util.concurrent.ScheduledExecutorService
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
  // TODO(cpovirk): Return ListenableScheduledFuture?
  public static <O extends @Nullable Object> ListenableFuture<O> scheduleAsync(
      AsyncCallable<O> callable,
      long delay,
      TimeUnit timeUnit,

   * @throws IllegalStateException if the service manager reaches a state from which it cannot
   *     become {@linkplain #isHealthy() healthy}.
   */
  @SuppressWarnings("GoodTime") // should accept a java.time.Duration
  public void awaitHealthy(long timeout, TimeUnit unit) throws TimeoutException {
    state.awaitHealthy(timeout, unit);
  }

  /**

    }
  }

  /**
   * Verifies that a collection is immutable.
   *
   * <p>A collection is considered immutable if:
   *
   * <ol>
   *   <li>All its mutation methods result in UnsupportedOperationException, and do not change the
   *       underlying contents.
   *   <li>All methods that return objects that can indirectly mutate the collection throw

/**
 * Standard implementation of {@link MutableValueGraph} that supports both directed and undirected
 * graphs. Instances of this class should be constructed with {@link ValueGraphBuilder}.
 *
 * <p>Time complexities for mutation methods are all O(1) except for {@code removeNode(N node)},
 * which is in O(d_node) where d_node is the degree of {@code node}.
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 * @author Omar Darwish

     *
     * @param loadTime the number of nanoseconds the cache spent computing or retrieving the new
     *     value
     */
    @SuppressWarnings("GoodTime") // should accept a java.time.Duration
    void recordLoadSuccess(long loadTime);

    /**
     * Records the failed load of a new entry. This should be called when a cache request causes an

   * such as:
   *
   * - Make checkOpen return the non-null `seq`. Then callers can assign that to a local variable or
   *   even back to `this.seq`. However, that may suggest that we're defending against concurrent
   *   mutation, which is not an actual risk because we use `synchronized`.
   * - Make `remaining` require a non-null `seq` argument. But this is a bit weird because the

/**
 * Standard implementation of {@link MutableNetwork} that supports both directed and undirected
 * graphs. Instances of this class should be constructed with {@link NetworkBuilder}.
 *
 * <p>Time complexities for mutation methods are all O(1) except for {@code removeNode(N node)},
 * which is in O(d_node) where d_node is the degree of {@code node}.
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 * @author Omar Darwish

   * insertion order.
   */
  private void populateTShapedGraph() {
    putEdge(2, 1);
    putEdge(1, 4);
    putEdge(1, 3);
    putEdge(1, 2); // Duplicate
    putEdge(4, 5);
  }

  // Element Mutation

  @Test
  public void putEdge_existingNodes() {
    assume().that(graphIsMutable()).isTrue();

    // Adding nodes initially for safety (insulating from possible future
    // modifications to proxy methods)