extends AbstractContainerTester<M, Entry<K, V>> {

  private M multimap;

  protected M multimap() {
    return multimap;
  }

  /**
   * @return an array of the proper size with {@code null} as the key of the middle element.
   */
  protected Entry<K, V>[] createArrayWithNullKey() {
    Entry<K, V>[] array = createSamplesArray();
    int nullKeyLocation = getNullLocation();

    throw new UnsupportedOperationException();
  }

  /**
   * Not supported. <b>You are attempting to create a multiset that may contain a non-{@code
   * Comparable} element.</b> Proper calls will resolve to the version in {@code
   * ImmutableSortedMultiset}, not this dummy version.
   *
   * @throws UnsupportedOperationException always

                 * Threads from our private pool are never interrupted. Threads from a
                 * user-supplied executor might be, but... what can we do? This is another reason
                 * to return a proper ListenableFuture instead of using listenInPoolThread.
                 */
                getUninterruptibly(delegate);
              } catch (Throwable t) {

    }

    try {
      FluentIterable.from(Lists.newArrayList("a", "b", "c")).get(3);
      fail();
    } catch (IndexOutOfBoundsException expected) {
    }
  }

  /*
   * Full and proper black-box testing of a Stream-returning method is extremely involved, and is
   * overkill when nearly all Streams are produced using well-tested JDK calls. So, we cheat and
   * just test that the toArray() contents are as expected.

   */
  public final boolean isEmpty() {
    return !getDelegate().iterator().hasNext();
  }

  /**
   * Returns an {@code ImmutableList} containing all of the elements from this fluent iterable in
   * proper sequence.
   *
   * <p><b>{@code Stream} equivalent:</b> {@code ImmutableList.copyOf(stream.iterator())}, or pass
   * {@link ImmutableList#toImmutableList} to {@code stream.collect()}.
   *

  /**
   * The HTTP <a href="https://goo.gl/VKpXxa">{@code X-Download-Options}</a> header field name.
   *
   * <p>When the new X-Download-Options header is present with the value {@code noopen}, the user is
   * prevented from opening a file download directly; instead, they must first save the file
   * locally.
   *
   * @since 24.1
   */