return array;
  }

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