docs: public final void updateFilterMap(Map<String,Object> propFilter)
      {
          if (propFilter == null)
              propFilter = new HashMap<String,Object>();     // Then handleUpdateFilterMap can modify the filter
          propFilter = this.handleUpdateFilterMap(propFilter);   // Update this object's local filter.
          this.setFilterMap(propFilter);            // Update any remote copy of this.
      }