public TrackedEntityInstanceQueryParams addFiltersIfNotExist(List<QueryItem> filtrs){
  for (  QueryItem filter : filtrs) {
    if (filters != null && !filters.contains(filter)) {
      filters.add(filter);
    }
  }
  return this;
}

public TrackedEntityInstanceQueryParams addFiltersIfNotExist ( List < QueryItem > filtrs ) { for ( QueryItem filter : filtrs ) { if ( filters != null && ! filters . contains ( filter ) ) { filters . add ( filter ) ; } } return this ; }
adds the given filters to this parameters if they are not already present .
