/**
   * Add a shutdown hook to wait for thread completion in the given {@link ExecutorService service}.
   * This is useful if the given service uses daemon threads, and we want to keep the JVM from
   * exiting immediately on shutdown, instead giving these daemon threads a chance to terminate
   * normally.
   *
   * @param service ExecutorService which uses daemon threads

  }

  /**
   * Creates and returns a new builder, configured to build {@code MinMaxPriorityQueue} instances
   * that are limited to {@code maximumSize} elements. Each time a queue grows beyond this bound, it
   * immediately removes its greatest element (according to its comparator), which might be the
   * element that was just added.
   */
  @SuppressWarnings("rawtypes") // https://github.com/google/guava/issues/989

    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);
    limiter.acquire(); // R0.00
    stopwatch.sleepMillis(200); // U0.20, we are ready for the next request...
    limiter.acquire(); // R0.00, ...which is granted immediately
    limiter.acquire(); // R0.20
    assertEvents("R0.00", "U0.20", "R0.00", "R0.20");
  }

  public void testSimpleAcquireReturnValues() {
    RateLimiter limiter = RateLimiter.create(5.0, stopwatch);

  // Views

  /**
   * Returns the set of distinct elements contained in this multiset. The element set is backed by
   * the same data as the multiset, so any change to either is immediately reflected in the other.
   * The order of the elements in the element set is unspecified.
   *
   * <p>If the element set supports any removal operations, these necessarily cause <b>all</b>

    // need to handle RejectedExecutionException

    if (allMustSucceed) {
      // We need fail fast, so we have to keep track of which future failed so we can propagate
      // the exception immediately

      // Register a listener on each Future in the list to update the state of this future.
      // Note that if all the futures on the list are done prior to completing this loop, the last

   * build-system quirks.
   */
  private @interface GwtTransient {}

  /**
   * Compares strings in natural order except that null comes immediately before a given value. This
   * works better than Ordering.natural().nullsFirst() because, if null comes before all other
   * values, it lies outside the submap/submultiset ranges we test, and the variety of tests that

     * course of a call to {@code remove()}. Thus, the expectation doesn't hold that {@code
     * map.remove(x)} returns the same value which {@code map.get(x)} did immediately beforehand.
     */
    @Override
    public void testRemove() {
      final Map<String, Map<Integer, Character>> map;
      final String keyToRemove;
      try {
        map = makePopulatedMap();

 * together. Any creation method that would customarily respect insertion order (such as {@link
 * #copyOf(Multimap)}) instead preserves key-grouped order by inserting entries for an existing key
 * immediately after the last entry having that key.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *
 * @author Jared Levy

 * together. Any creation method that would customarily respect insertion order (such as {@link
 * #copyOf(Multimap)}) instead preserves key-grouped order by inserting entries for an existing key
 * immediately after the last entry having that key.
 *
 * <p>See the Guava User Guide article on <a href=
 * "https://github.com/google/guava/wiki/ImmutableCollectionsExplained">immutable collections</a>.
 *
 * @author Jared Levy

   *     arbitrary past or present time
   */
  abstract long queryEarliestAvailable(long nowMicros);

  /**
   * Reserves the requested number of permits and returns the time that those permits can be used
   * (with one caveat).
   *
   * @return the time that the permits may be used, or, if the permits may be used immediately, an
   *     arbitrary past or present time