assertTrue(listener.isEmpty());

    Object one = new Object();
    Object two = new Object();
    Object three = new Object();
    Object four = new Object();
    Object five = new Object();
    Object six = new Object();

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

    assertTrue(listener.isEmpty());

    Object one = new Object();
    Object two = new Object();
    Object three = new Object();
    Object four = new Object();
    Object five = new Object();
    Object six = new Object();

    map.put(one, two);
    map.remove(one);
    assertNotified(listener, one, two, RemovalCause.EXPLICIT);

   *     is to be used to sort the new map
   * @return a new {@code TreeMap} initialized with the mappings from {@code map} and using the
   *     comparator of {@code map}
   */
  public static <K extends @Nullable Object, V extends @Nullable Object> TreeMap<K, V> newTreeMap(
      SortedMap<K, ? extends V> map) {
    return new TreeMap<>(map);
  }

  /**

          throw new IllegalStateException("Cannot call finishToValueAndCloser() twice");

        case OPEN:
          break;
      }
      throw new AssertionError(state);
    }
    future.addListener(
        new Runnable() {
          @Override
          public void run() {
            provideValueAndCloser(consumer, ClosingFuture.this);
          }
        },