code: public DelimiterWriterFactory addColumnTitle(final String columnTitle) {
          final Map<String, Object> columnMapping = this.getColumnMapping();
          final List<ColumnMetaData> columnMetaDatas = (List<ColumnMetaData>) columnMapping.get(FPConstants.DETAIL_ID);
          final Map<Integer, String> columnIndices = (Map<Integer, String>) columnMapping.get(FPConstants.COL_IDX);
  
          final ColumnMetaData metaData = new ColumnMetaData();
          metaData.setColName(columnTitle);
          columnMetaDatas.add(metaData);
  
          final Integer columnIndex = columnMetaDatas.indexOf(metaData);
          columnIndices.put(columnIndex, columnTitle);
          return this;
      }
docs: TODO DO: check that no column titles can be added after first nextRecord