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);

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

    map.put(three, four);

    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);

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

    map.put(three, four);

  `Well, I should like to be a LITTLE larger, sir, if you
wouldn't mind,' said Alice:  `three inches is such a wretched
height to be.'

  `It is a very good height indeed!' said the Caterpillar
angrily, rearing itself upright as it spoke (it was exactly three
inches high).

  `But I'm not used to it!' pleaded poor Alice in a piteous tone.

      Combiner2<V1, V2> whenAllSucceed(ClosingFuture<V1> future1, ClosingFuture<V2> future2) {
    return new Combiner2<>(future1, future2);
  }

  /**
   * Starts specifying how to combine three {@link ClosingFuture}s into a single pipeline, assuming
   * they all succeed. If any fail, the resulting pipeline will fail.
   *
   * <p>Calling this method allows you to use lambdas or method references typed with the types of

      MockResponse(
        code = 401,
        headers = headersOf("WWW-Authenticate", "Basic realm=\"protected area\""),
        body = "Please authenticate.",
      )
    // Fail auth three times...
    server.enqueue(pleaseAuthenticate)
    server.enqueue(pleaseAuthenticate)
    server.enqueue(pleaseAuthenticate)
    // ...then succeed the fourth time.
    server.enqueue(