} while (stopwatch.elapsed(SECONDS) < 1);
          }
        };

    List<Throwable> exceptions = runThreadsAndReturnExceptions(numThreads, task);

    assertThat(exceptions).isEmpty();
  }

  private static List<Throwable> runThreadsAndReturnExceptions(int numThreads, Runnable task) {
    List<Thread> threads = new ArrayList<>(numThreads);

    return listIterator(0);
  }

  @SuppressWarnings("unchecked")
  @Override
  public UnmodifiableListIterator<E> listIterator(int index) {
    checkPositionIndex(index, size());
    if (isEmpty()) {
      return (UnmodifiableListIterator<E>) EMPTY_ITR;
    } else {
      return new Itr<E>(this, index);
    }
  }

  /** A singleton implementation of iterator() for the empty ImmutableList. */

		globalEtcdClient, err = etcd.New(etcdCfg)
		if err != nil {
			configLogIf(ctx, fmt.Errorf("Unable to initialize etcd config: %w", err))
		}

		if len(globalDomainNames) != 0 && !globalDomainIPs.IsEmpty() && globalEtcdClient != nil {
			if globalDNSConfig != nil {
				// if global DNS is already configured, indicate with a warning, in case
				// users are confused.

    Iterator<String> cycle = Iterators.cycle(iterable);
    assertTrue(cycle.hasNext());
    assertEquals("a", cycle.next());
    assertTrue(cycle.hasNext());
    cycle.remove();
    assertTrue(iterable.elements.isEmpty());
    assertFalse(cycle.hasNext());
  }

  public void testCycleNoSuchElementException() {
    Iterable<String> iterable = Lists.newArrayList("a");
    Iterator<String> cycle = Iterators.cycle(iterable);

    @Override
    public Collection<V2> get(@ParametricNullness final K key) {
      return transform(key, fromMultimap.get(key));
    }

    @Override
    public boolean isEmpty() {
      return fromMultimap.isEmpty();
    }

    @Override
    Set<K> createKeySet() {
      return fromMultimap.keySet();
    }

    @Override
    Multiset<K> createKeys() {

    // notification.
    assertEquals(expectedKeys, Sets.union(cache.asMap().keySet(), removalNotifications.keySet()));
    assertTrue(Sets.intersection(cache.asMap().keySet(), removalNotifications.keySet()).isEmpty());
    threadPool.shutdown();
    threadPool.awaitTermination(300, SECONDS);
  }

  /**
   * Calls get() repeatedly from many different threads, and tests that all of the removed entries

   *     are any duplicate services.
   */
  public ServiceManager(Iterable<? extends Service> services) {
    ImmutableList<Service> copy = ImmutableList.copyOf(services);
    if (copy.isEmpty()) {
      // Having no services causes the manager to behave strangely. Notably, listeners are never
      // fired. To avoid this we substitute a placeholder service.
      logger
          .get()
          .log(

   * already-validated InternetDomainName, as in {@link ancestor}.
   */
  private InternetDomainName(String name, ImmutableList<String> parts) {
    checkArgument(!parts.isEmpty(), "Cannot create an InternetDomainName with zero parts.");
    this.name = name;
    this.parts = parts;
  }

  /**

    List<HashFunction> list = new ArrayList<>();
    for (HashFunction hashFunction : hashFunctions) {
      list.add(hashFunction);
    }
    checkArgument(!list.isEmpty(), "number of hash functions (%s) must be > 0", list.size());
    return new ConcatenatedHashFunction(list.toArray(new HashFunction[0]));
  }

   *     are any duplicate services.
   */
  public ServiceManager(Iterable<? extends Service> services) {
    ImmutableList<Service> copy = ImmutableList.copyOf(services);
    if (copy.isEmpty()) {
      // Having no services causes the manager to behave strangely. Notably, listeners are never
      // fired. To avoid this we substitute a placeholder service.
      logger
          .get()
          .log(