/** Standard constructor. */
  protected AbstractMapBasedMultiset(Map<E, Count> backingMap) {
    checkArgument(backingMap.isEmpty());
    this.backingMap = backingMap;
  }

  /** Used during deserialization only. The backing map must be empty. */
  void setBackingMap(Map<E, Count> backingMap) {
    this.backingMap = backingMap;
  }

  // Required Implementations

  /**
   * {@inheritDoc}
   *

  static class StandardImplForwardingMap<K, V> extends ForwardingMap<K, V> {
    private final Map<K, V> backingMap;

    StandardImplForwardingMap(Map<K, V> backingMap) {
      this.backingMap = backingMap;
    }

    @Override
    protected Map<K, V> delegate() {
      return backingMap;
    }

    @Override
    public boolean containsKey(Object key) {
      return standardContainsKey(key);
    }

  ConcurrentMap<String, AtomicInteger> backingMap;
  ConcurrentHashMultiset<String> multiset;

  @SuppressWarnings("unchecked")
  @Override
  protected void setUp() {
    backingMap = mock(ConcurrentMap.class);
    when(backingMap.isEmpty()).thenReturn(true);

    multiset = ConcurrentHashMultiset.create(backingMap);
  }

  public void testCount_elementPresent() {

    checkArgument(backingMap.isEmpty());
    checkNotNull(factory);
    // TODO(jlevy): Wrap factory to validate that the supplied maps are empty?
    return new StandardTable<>(backingMap, factory);
  }

  /**
   * Returns a view of a table where each value is transformed by a function. All other properties
   * of the table, such as iteration order, are left intact.
   *

 */
@GwtCompatible
class StandardTable<R, C, V> extends AbstractTable<R, C, V> implements Serializable {
  final Map<R, Map<C, V>> backingMap;
  final Supplier<? extends Map<C, V>> factory;

  StandardTable(Map<R, Map<C, V>> backingMap, Supplier<? extends Map<C, V>> factory) {
    this.backingMap = backingMap;
    this.factory = factory;
  }

  // Accessors

  @Override

    checkArgument(backingMap.isEmpty());
    checkNotNull(factory);
    // TODO(jlevy): Wrap factory to validate that the supplied maps are empty?
    return new StandardTable<>(backingMap, factory);
  }

  /**
   * Returns a view of a table where each value is transformed by a function. All other properties
   * of the table, such as iteration order, are left intact.
   *

 */
@GwtCompatible
class StandardTable<R, C, V> extends AbstractTable<R, C, V> implements Serializable {
  final Map<R, Map<C, V>> backingMap;
  final Supplier<? extends Map<C, V>> factory;

  StandardTable(Map<R, Map<C, V>> backingMap, Supplier<? extends Map<C, V>> factory) {
    this.backingMap = backingMap;
    this.factory = factory;
  }

  // Accessors

  @Override

        ObjectCountHashMap<? extends E> backingMap = tryGetMap(multiset);
        if (backingMap != null) {
          contents.ensureCapacity(Math.max(contents.size(), backingMap.size()));
          for (int i = backingMap.firstIndex(); i >= 0; i = backingMap.nextIndex(i)) {
            addCopies(backingMap.getKey(i), backingMap.getValue(i));
          }
        } else {

    // If the row was previously empty, we check if there's a new row here every time we're queried.
    void updateWholeRowField() {
      if (wholeRow == null || (wholeRow.isEmpty() && backingMap.containsKey(rowKey))) {
        wholeRow = (SortedMap<C, V>) backingMap.get(rowKey);
      }
    }

    @Override
    @Nullable SortedMap<C, V> computeBackingRowMap() {
      updateWholeRowField();
      SortedMap<C, V> map = wholeRow;

    // If the row was previously empty, we check if there's a new row here every time we're queried.
    void updateWholeRowField() {
      if (wholeRow == null || (wholeRow.isEmpty() && backingMap.containsKey(rowKey))) {
        wholeRow = (SortedMap<C, V>) backingMap.get(rowKey);
      }
    }

    @Override
    @Nullable SortedMap<C, V> computeBackingRowMap() {
      updateWholeRowField();
      SortedMap<C, V> map = wholeRow;