code: public BatchMutation<K> addSuperInsertion(K key, List<String> columnFamilies,
        SuperColumn superColumn) {
      Mutation mutation = new Mutation();
      mutation.setColumn_or_supercolumn(new ColumnOrSuperColumn().setSuper_column(superColumn));
      addMutation(key, columnFamilies, mutation);
      return this;
    }
docs: Add a SuperColumn insertion (or update) to the batch mutation request.