code: private Object writeTable(SerIterator itemIterator) {
          List<Object> result = new ArrayList<>();
          while (itemIterator.hasNext()) {
              itemIterator.next();
              Object outputKey = writeObject(itemIterator.keyType(), itemIterator.key(), null);
              Object outputCol = writeObject(itemIterator.columnType(), itemIterator.column(), null);
              Object outputValue = writeObject(itemIterator.valueType(), itemIterator.value(), itemIterator);
              result.add(Arrays.asList(outputKey, outputCol, outputValue));
          }
          return result;
      }
docs: write table