boolean sameComparator,
      Iterable<? extends Entry<? extends K, ? extends V>> entries) {
    // "adding" type params to an array of a raw type should be safe as
    // long as no one can ever cast that same array instance back to a
    // raw type.
    @SuppressWarnings("unchecked")
    Entry<K, V>[] entryArray = (Entry[]) Iterables.toArray(entries, EMPTY_ENTRY_ARRAY);

   * then:
   *
   * <ul>
   *   <li>{@code isDone()} must return {@code true}
   *   <li>{@code isCancelled()} must return {@code false}
   *   <li>{@code get()} must not block, and it must throw an {@code ExecutionException} with the
   *       return value of this method as its cause
   * </ul>
   *
   * <p>This method is {@code protected} so that classes like {@code

      boolean sameComparator,
      Iterable<? extends Entry<? extends K, ? extends V>> entries) {
    // "adding" type params to an array of a raw type should be safe as
    // long as no one can ever cast that same array instance back to a
    // raw type.
    @SuppressWarnings("unchecked")
    Entry<K, V>[] entryArray = (Entry[]) Iterables.toArray(entries, EMPTY_ENTRY_ARRAY);

   * {@code tailSet} views.
   *
   * <pre>{@code
   * NavigableSet<E> set = synchronizedNavigableSet(new TreeSet<E>());
   *  ...
   * synchronized (set) {
   *   // Must be in the synchronized block
   *   Iterator<E> it = set.iterator();
   *   while (it.hasNext()) {
   *     foo(it.next());
   *   }
   * }
   * }</pre>
   *
   * <p>or:
   *
   * <pre>{@code

      return toArrayList(this).toArray(a);
    }
  }

  private static <E> ArrayList<E> toArrayList(Collection<E> c) {
    // Avoid calling ArrayList(Collection), which may call back into toArray.
    ArrayList<E> result = new ArrayList<>(c.size());
    Iterators.addAll(result, c.iterator());
    return result;
  }

  // Serialization Support

   * the {@code Future} is already done. Second, if buggy code calls {@code getDone} on a {@code
   * Future} that is still pending, the program will throw instead of block. This can be important
   * for APIs like {@link #whenAllComplete whenAllComplete(...)}{@code .}{@link
   * FutureCombiner#call(Callable, Executor) call(...)}, where it is easy to use a new input from

    }
    // array is covariant. component type is super type, so is the array type.
    @SuppressWarnings("unchecked") // going from raw type back to generics
    /*
     * requireNonNull is safe because we call getArraySupertype only after checking
     * supertype.isArray().
     */
    TypeToken<?> componentSupertype =

   *     HashMultimap.<K, V>create());
   * ...
   * Collection<V> values = multimap.get(key);  // Needn't be in synchronized block
   * ...
   * synchronized (multimap) {  // Synchronizing on multimap, not values!
   *   Iterator<V> i = values.iterator(); // Must be in synchronized block
   *   while (i.hasNext()) {
   *     foo(i.next());
   *   }
   * }
   * }</pre>
   *

  @GwtIncompatible // java.time.Duration
  @SuppressWarnings("GoodTime") // duration decomposition
  private static long toNanosSaturated(java.time.Duration duration) {
    // Using a try/catch seems lazy, but the catch block will rarely get invoked (except for
    // durations longer than approximately +/- 292 years).
    try {
      return duration.toNanos();
    } catch (ArithmeticException tooBig) {