*/
    @Override
    @CanIgnoreReturnValue
    public Builder<E> add(E element) {
      checkNotNull(element);
      if (hashTable != null && chooseTableSize(size) <= hashTable.length) {
        addDeduping(element);
        return this;
      } else {
        hashTable = null;
        super.add(element);
        return this;
      }
    }

    /**