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();

  protected void expectMissingValues(V... elements) {
    for (V element : elements) {
      assertFalse("Should not contain value " + element, getMap().containsValue(element));
    }
  }

  /** @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();

    return collection;
  }

  /** @see AbstractContainerTester#resetContainer() */
  protected void resetCollection() {
    resetContainer();
  }

  /** @return an array of the proper size with {@code null} inserted into the middle element. */
  protected E[] createArrayWithNullElement() {
    E[] array = createSamplesArray();
    array[getNullLocation()] = null;
    return array;
  }

  protected void expectMissingValues(V... elements) {
    for (V element : elements) {
      assertFalse("Should not contain value " + element, getMap().containsValue(element));
    }
  }

  /** @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();

 *   <li>remove();
 *   <li>next();
 * </ol>
 *
 * <p>This particular order of operations may be unrealistic, and testing all 3^5 of them may be
 * thought of as overkill; however, it's difficult to determine which proper subset of this massive
 * set would be sufficient to expose any possible bug. Brute force is simpler.
 *
 * <p>To use this class the concrete subclass must implement the {@link

    private ArrayWithDuplicate(E[] elements, E duplicate) {
      this.elements = elements;
      this.duplicate = duplicate;
    }
  }

  /**
   * @return an array of the proper size with a duplicate element. The size must be at least three.
   */
  protected ArrayWithDuplicate<E> createArrayWithDuplicateElement() {
    E[] elements = createSamplesArray();

    return collection;
  }

  /** @see AbstractContainerTester#resetContainer() */
  protected void resetCollection() {
    resetContainer();
  }

  /** @return an array of the proper size with {@code null} inserted into the middle element. */
  protected E[] createArrayWithNullElement() {
    E[] array = createSamplesArray();
    array[getNullLocation()] = null;
    return array;
  }

 *   <li>remove();
 *   <li>next();
 * </ol>
 *
 * <p>This particular order of operations may be unrealistic, and testing all 3^5 of them may be
 * thought of as overkill; however, it's difficult to determine which proper subset of this massive
 * set would be sufficient to expose any possible bug. Brute force is simpler.
 *
 * <p>To use this class the concrete subclass must implement the {@link

    private ArrayWithDuplicate(E[] elements, E duplicate) {
      this.elements = elements;
      this.duplicate = duplicate;
    }
  }

  /**
   * @return an array of the proper size with a duplicate element. The size must be at least three.
   */
  protected ArrayWithDuplicate<E> createArrayWithDuplicateElement() {
    E[] elements = createSamplesArray();

    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();