code: @EventHandler
      public void onSelectFilter(SelectFilterEvent selectFilterEvent){
          for (FacetWidget facetWidget : filterList) {
              if(facetWidget.getFacetField().equals(selectFilterEvent.getFilterName())){
                  for (FacetWidgetItem facetWidgetItem : facetWidget.getFacetWidgetItems()) {
                      if(facetWidgetItem.getValue().equals(selectFilterEvent.getFilterValue())){
                          facetWidget.selectItems(Arrays.asList(facetWidgetItem));
                      }
                  }
              }
          }
  
      }
docs: When a SelectFilterEvent is triggered, this method will look for the filter and value and will select it.