}

  public void testRemoveAll() {
    List<String> list = newArrayList("a", "b", "c", "d", "e");
    assertTrue(Iterators.removeAll(list.iterator(), newArrayList("b", "d", "f")));
    assertEquals(newArrayList("a", "c", "e"), list);
    assertFalse(Iterators.removeAll(list.iterator(), newArrayList("x", "y", "z")));
    assertEquals(newArrayList("a", "c", "e"), list);
  }

  public void testRemoveIf() {

  }

  public void testRemoveAll() {
    List<String> list = newArrayList("a", "b", "c", "d", "e");
    assertTrue(Iterators.removeAll(list.iterator(), newArrayList("b", "d", "f")));
    assertEquals(newArrayList("a", "c", "e"), list);
    assertFalse(Iterators.removeAll(list.iterator(), newArrayList("x", "y", "z")));
    assertEquals(newArrayList("a", "c", "e"), list);
  }

  public void testRemoveIf() {

   */
  @GwtIncompatible // Array.newInstance(Class, int)
  public static <T extends @Nullable Object> T[] toArray(
      Iterator<? extends T> iterator, Class<@NonNull T> type) {
    List<T> list = Lists.newArrayList(iterator);
    return Iterables.<T>toArray(list, type);
  }

  /**
   * Adds all elements in {@code iterator} to {@code collection}. The iterator will be left

    // quadratic cost of adding them to the COWAS directly.
    Collection<? extends E> elementsCollection =
        (elements instanceof Collection)
            ? (Collection<? extends E>) elements
            : Lists.newArrayList(elements);
    return new CopyOnWriteArraySet<>(elementsCollection);
  }

  /**
   * Creates an {@code EnumSet} consisting of all enum values that are not in the specified