@Override
  public int size() {
    return totalSize;
  }

  @Override
  public boolean containsKey(@CheckForNull Object key) {
    return map.containsKey(key);
  }

  // Modification Operations

  @Override
  public boolean put(@ParametricNullness K key, @ParametricNullness V value) {
    Collection<V> collection = map.get(key);
    if (collection == null) {

  @Override
  public int size() {
    return totalSize;
  }

  @Override
  public boolean containsKey(@CheckForNull Object key) {
    return map.containsKey(key);
  }

  // Modification Operations

  @Override
  public boolean put(@ParametricNullness K key, @ParametricNullness V value) {
    Collection<V> collection = map.get(key);
    if (collection == null) {