@Override
protected void execDecorateRow(ITableRow row) throws ProcessingException {
  if(/*some condition indicates the row is bold*/( {
    row.setFont(boldFontSpec);
  }
}

row.setFont(FontSpec.parse("bold"));

    @Override
    protected void execDecorateCell(Cell view, ITableRow row, IColumn<?> col) throws ProcessingException {
      row.getCellForUpdate(col).setFont(view.getFont().getBoldCopy());
    }