code: private Iterable<Map<GoogleWebmasterFilter.Dimension, ApiDimensionFilter>> getFilterGroups(WorkUnitState wuState) {
      List<Map<GoogleWebmasterFilter.Dimension, ApiDimensionFilter>> filters = new ArrayList<>();
      for (String filter : splitter.split(wuState.getProp(GoogleWebMasterSource.KEY_REQUEST_FILTERS))) {
        String[] parts = Iterables.toArray(Splitter.on(".").split(filter), String.class);
        String dimString = parts[0].toUpperCase();
        String valueString = parts[1].toUpperCase();
  
        GoogleWebmasterFilter.Dimension dimension = GoogleWebmasterFilter.Dimension.valueOf(dimString);
        Map<GoogleWebmasterFilter.Dimension, ApiDimensionFilter> map = new HashMap<>();
  
        if (dimension == GoogleWebmasterFilter.Dimension.COUNTRY) {
          map.put(GoogleWebmasterFilter.Dimension.COUNTRY, GoogleWebmasterFilter.countryEqFilter(valueString));
        } else {
          throw new UnsupportedOperationException("Only country filter is supported for now");
        }
        filters.add(map);
      }
      return filters;
    }
docs: Currently, the filter group is just one filter at a time, there is no cross-dimension filters combination.
  TODO: May need to implement this feature in the future based on use cases.