code: public void writeVisibleDataStyles(final XMLUtil util, final Appendable appendable)
              throws IOException {
          final Iterable<DataStyle> dataStyles = this.dataStylesContainer
                  .getValues(Dest.STYLES_COMMON_STYLES);
          for (final DataStyle dataStyle : dataStyles) {
              assert !dataStyle.isHidden() : dataStyle.toString() + " - " + dataStyle.getName() +
                      TableCellStyle.DEFAULT_CELL_STYLE.toString();
  
              dataStyle.appendXMLContent(util, appendable);
          }
      }
docs: Write data styles to styles.xml/common-styles
  
  @param util   an util
  @param appendable the destination
  @throws IOException if an I/O error occurs