CreateWeight() public method

public CreateWeight ( Searcher searcher ) : Weight
searcher Lucene.Net.Search.Searcher
return Lucene.Net.Search.Weight
FunctionQuery Class Documentation
Example #1
0
        public void CreateSpatialFilterAndWeight(PointRadiusCriterion geoFilter, Filter currentFilter, Weight currentWeight)
        {
            var spatialContext = SpatialContext.GEO;
            var geohashTree = new GeohashPrefixTree(spatialContext, 10);
            var strategy = new RecursivePrefixTreeStrategy(geohashTree, geoFilter.FieldName);
            var point = spatialContext.MakePoint(geoFilter.Longitude, geoFilter.Latitude);

            var spatialArgs = new SpatialArgs(SpatialOperation.Intersects, spatialContext.MakeCircle(point,
                DistanceUtils.Dist2Degrees(geoFilter.RadiusKm, DistanceUtils.EARTH_MEAN_RADIUS_KM)));

            var circle = spatialContext.MakeCircle(point,
                    DistanceUtils.Dist2Degrees(geoFilter.RadiusKm, DistanceUtils.EARTH_MEAN_RADIUS_KM));
            var circleCells = strategy.GetGrid().GetWorldNode().GetSubCells(circle);

            var luceneFilters = new List<Filter>();
            if (currentFilter != null)
                luceneFilters.Add(currentFilter);

            var tempSpatial = strategy.MakeFilter(spatialArgs);
                luceneFilters.Add(tempSpatial);
            
            if (geoFilter.Sort != PointRadiusCriterion.SortOption.None)
            {
                var valueSource = strategy.MakeDistanceValueSource(point);
                var funcQ = new FunctionQuery(valueSource);
                // this is a bit odd... but boosting the score negatively orders results 
                if (geoFilter.Sort == PointRadiusCriterion.SortOption.Ascending)
                {
                    funcQ.Boost = -1;
                }
                spatialWeight = funcQ.CreateWeight(this);
                spatialWeight.GetSumOfSquaredWeights();

                luceneFilters.Add(new QueryWrapperFilter(currentWeight.Query));
            }

            spatialFilter = new ChainedFilter(luceneFilters.ToArray(), 1);
        }