public void addCssClass(String cssClass) {
   if (this.isHeaderColumn) {
     StringBuilder cssClassSb =
         DatatableOptions.CSSCLASS.valueFrom(this.columnConfiguration.getOptions());
     if (cssClassSb != null && cssClassSb.length() != 0) {
       DatatableOptions.CSSCLASS.appendIn(this.columnConfiguration.getOptions(), CLASS_SEPARATOR);
     }
     DatatableOptions.CSSCLASS.appendIn(this.columnConfiguration.getOptions(), cssClass);
   } else {
     if (this.cssClass == null) {
       this.cssClass = new StringBuilder();
     } else {
       this.cssClass.append(CLASS_SEPARATOR);
     }
     this.cssClass.append(cssClass);
   }
 }
  @Override
  protected StringBuilder getHtmlAttributes() {
    StringBuilder html = new StringBuilder();
    if (this.isHeaderColumn) {
      html.append(
          writeAttribute(
              "class",
              DatatableOptions.CSSCLASS.valueFrom(this.getColumnConfiguration().getOptions())));
      html.append(
          writeAttribute(
              "style",
              DatatableOptions.CSSSTYLE.valueFrom(this.getColumnConfiguration().getOptions())));

      String columnId = DatatableOptions.ID.valueFrom(this.getColumnConfiguration().getOptions());
      if (StringUtils.isNotBlank(columnId)) {
        html.append(writeAttribute("id", columnId));
      }
    } else {
      html.append(writeAttribute("class", this.cssCellClass));
      html.append(writeAttribute("style", this.cssCellStyle));
    }
    return html;
  }