* classes like LinkedHashMultimap that need to say something different are
   * still able to {@inheritDoc} all the way from Multimap?
   */

  @Override
  Multiset<K> createKeys() {
    return new Multimaps.Keys<K, V>(this);
  }

  /**
   * {@inheritDoc}
   *
   * <p>The iterator generated by the returned collection traverses the values for one key, followed

  @Override
  public final int count(@Nullable Object element) {
    return backingMap.get(element);
  }

  // Optional Operations - Modification Operations

  /**
   * {@inheritDoc}
   *
   * @throws IllegalArgumentException if the call would result in more than {@link
   *     Integer#MAX_VALUE} occurrences of {@code element} in this multiset.
   */
  @CanIgnoreReturnValue
  @Override

    //                                                                            Document
    //                                                                            ========
    /**
     * {@inheritDoc} <br>
     * Application Origin Methods:
     * <pre>
     * <span style="font-size: 130%; color: #553000">[Small Helper]</span>
     * o saveInfo() <span style="color: #3F7E5E">// save messages to session</span>

   */
  @Override
  public boolean isEmpty() {
    return rowList.isEmpty() || columnList.isEmpty();
  }

  /**
   * {@inheritDoc}
   *
   * @throws IllegalArgumentException if {@code rowKey} is not in {@link #rowKeySet()} or {@code
   *     columnKey} is not in {@link #columnKeySet()}.
   */
  @CanIgnoreReturnValue
  @Override

  @Override
  public int count(@Nullable Object element) {
    AtomicInteger existingCounter = safeGet(countMap, element);
    return (existingCounter == null) ? 0 : existingCounter.get();
  }

  /**
   * {@inheritDoc}
   *
   * <p>If the data in the multiset is modified by any other threads during this method, it is
   * undefined which (if any) of these modifications will be reflected in the result.
   */
  @Override