code: private Filter getFilter(String layerFilter, String[] featureIds) throws GeomajasException {
  		Filter filter = null;
  		if (null != layerFilter) {
  			filter = filterService.parseFilter(layerFilter);
  		}
  		if (null != featureIds) {
  			Filter fidFilter = filterService.createFidFilter(featureIds);
  			if (null == filter) {
  				filter = fidFilter;
  			} else {
  				filter = filterService.createAndFilter(filter, fidFilter);
  			}
  		}
  		return filter;
  	}
docs: Build filter for the request.
  
  @param layerFilter layer filter
  @param featureIds features to include in report (null for all)
  @return filter
  @throws GeomajasException filter could not be parsed/created