code: protected void encodeColHeaders(final FacesContext context, final Sheet sheet, final WidgetBuilder wb)
                  throws IOException {
          final JavascriptVarBuilder vb = new JavascriptVarBuilder(null, false);
          for (final SheetColumn column : sheet.getColumns()) {
              if (!column.isRendered()) {
                  continue;
              }
              vb.appendArrayValue(column.getHeaderText(), true);
          }
          wb.nativeAttr("colHeaders", vb.closeVar().toString());
      }
docs: Encode the column headers
  
  @param context
  @param sheet
  @param wb
  @throws IOException