code: public void filterReset(String columnId) {
          if (displayerSettings.isFilterEnabled()) {
  
              columnSelectionMap.remove(columnId);
              DataSetGroup groupOp = dataSetHandler.getGroupOperation(columnId);
  
              // Notify to those interested parties the reset event.
              if (displayerSettings.isFilterNotificationEnabled()) {
                  for (DisplayerListener listener : listenerList) {
                      listener.onFilterReset(this, Arrays.asList(groupOp));
                  }
              }
              // Apply the selection to this displayer
              if (displayerSettings.isFilterSelfApplyEnabled()) {
                  dataSetHandler.drillUp(groupOp);
                  redraw();
              }
          }
      }
docs: Clear any filter on the given column.
  
  @param columnId The name of the column to reset.