* keys and values are the result of applying the provided mapping functions to the input
   * elements. The generated map is sorted by the specified comparator.
   *
   * <p>If the mapped keys contain duplicates (according to the specified comparator), an {@code
   * IllegalArgumentException} is thrown when the collection operation is performed. (This differs

    if (getClass().getName().startsWith("com.google.common.util.concurrent.")) {
      builder.append(getClass().getSimpleName());
    } else {
      builder.append(getClass().getName());
    }
    builder.append('@').append(toHexString(identityHashCode(this))).append("[status=");
    if (isCancelled()) {
      builder.append("CANCELLED");
    } else if (isDone()) {
      addDoneString(builder);
    } else {

   * keys and values are the result of applying the provided mapping functions to the input
   * elements. The generated map is sorted by the specified comparator.
   *
   * <p>If the mapped keys contain duplicates (according to the specified comparator), an {@code
   * IllegalArgumentException} is thrown when the collection operation is performed. (This differs

    }
    assertWithMessage("table size after adding " + size + " elements")
        .that(bucketsOf(map1))
        .isEqualTo(initialBuckets);

    /*
     * Something slightly different happens when the entries are added all at
     * once; make sure that passes too.
     */
    map2.putAll(map1);
    assertWithMessage("table size after adding " + size + " elements")
        .that(bucketsOf(map1))

    }
    assertWithMessage("table size after adding " + size + " elements")
        .that(bucketsOf(map1))
        .isEqualTo(initialBuckets);

    /*
     * Something slightly different happens when the entries are added all at
     * once; make sure that passes too.
     */
    map2.putAll(map1);
    assertWithMessage("table size after adding " + size + " elements")
        .that(bucketsOf(map1))

    StringBuilder buf = new StringBuilder((len * 3 / 2) + 16);

    int oldpos = 0;
    do {
      buf.append(string, oldpos, pos);
      buf.append(replacement);
      oldpos = pos + 1;
      pos = indexIn(string, oldpos);
    } while (pos != -1);

    buf.append(string, oldpos, len);
    return buf.toString();
  }

  /**

   */
  abstract <T> T getFinalValue(ClosingFuture<T> closingFuture) throws ExecutionException;

  /** Marks the given step final, cancels it, and waits for the cancellation to happen. */
  abstract void cancelFinalStepAndWait(ClosingFuture<TestCloseable> closingFuture);

  /**
   * Marks the given step final and waits for it to fail. Expects the failure exception to match

        tryDrainReferenceQueues();
        return null;
      }

      return value;
    }

    /**
     * Performs routine cleanup following a read. Normally cleanup happens during writes, or from
     * the cleanupExecutor. If cleanup is not observed after a sufficient number of reads, try
     * cleaning up from the read thread.
     */
    void postReadCleanup() {

    StringBuilder buf = new StringBuilder((len * 3 / 2) + 16);

    int oldpos = 0;
    do {
      buf.append(string, oldpos, pos);
      buf.append(replacement);
      oldpos = pos + 1;
      pos = indexIn(string, oldpos);
    } while (pos != -1);

    buf.append(string, oldpos, len);
    return buf.toString();
  }

  /**

  // operation in the constructor.
  //
  // 1. In the listener that performs the callback. In this case it is fine since inputFuture is
  //    assigned prior to calling addListener, and addListener happens-before any invocation of the
  //    listener. Notably, this means that 'volatile' is unnecessary to make 'inputFuture' visible
  //    to the listener.
  //