code: static <E> void populateMultiset(Multiset<E> multiset, ObjectInputStream stream)
        throws IOException, ClassNotFoundException {
      int distinctElements = stream.readInt();
      populateMultiset(multiset, stream, distinctElements);
    }
docs: Populates a multiset by reading an input stream, as part of deserialization. See {@link
  #writeMultiset} for the data format.