package org.apache.lucene.spatial.prefix;
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import com.spatial4j.core.shape.Shape;
import org.apache.lucene.search.Filter;
import org.apache.lucene.spatial.DisjointSpatialFilter;
import org.apache.lucene.spatial.prefix.tree.SpatialPrefixTree;
import org.apache.lucene.spatial.query.SpatialArgs;
import org.apache.lucene.spatial.query.SpatialOperation;
import org.apache.lucene.spatial.query.UnsupportedSpatialOperation;
/**
* A {@link PrefixTreeStrategy} which uses {@link AbstractVisitingPrefixTreeFilter}.
* This strategy has support for searching non-point shapes (note: not tested).
* Even a query shape with distErrPct=0 (fully precise to the grid) should have
* good performance for typical data, unless there is a lot of indexed data
* coincident with the shape's edge.
*
* @lucene.experimental
*/
public class RecursivePrefixTreeStrategy extends PrefixTreeStrategy {
private int prefixGridScanLevel;
public RecursivePrefixTreeStrategy(SpatialPrefixTree grid, String fieldName) {
super(grid, fieldName,
true);//simplify indexed cells
prefixGridScanLevel = grid.getMaxLevels() - 4;//TODO this default constant is dependent on the prefix grid size
}
/**
* Sets the grid level [1-maxLevels] at which indexed terms are scanned brute-force
* instead of by grid decomposition. By default this is maxLevels - 4. The
* final level, maxLevels, is always scanned.
*
* @param prefixGridScanLevel 1 to maxLevels
*/
public void setPrefixGridScanLevel(int prefixGridScanLevel) {
//TODO if negative then subtract from maxlevels
this.prefixGridScanLevel = prefixGridScanLevel;
}
@Override
public String toString() {
return getClass().getSimpleName()+"(prefixGridScanLevel:"+prefixGridScanLevel+",SPG:("+ grid +"))";
}
@Override
public Filter makeFilter(SpatialArgs args) {
final SpatialOperation op = args.getOperation();
if (op == SpatialOperation.IsDisjointTo)
return new DisjointSpatialFilter(this, args, getFieldName());
Shape shape = args.getShape();
int detailLevel = grid.getLevelForDistance(args.resolveDistErr(ctx, distErrPct));
final boolean hasIndexedLeaves = true;
if (op == SpatialOperation.Intersects) {
return new IntersectsPrefixTreeFilter(
shape, getFieldName(), grid, detailLevel, prefixGridScanLevel,
hasIndexedLeaves);
} else if (op == SpatialOperation.IsWithin) {
return new WithinPrefixTreeFilter(
shape, getFieldName(), grid, detailLevel, prefixGridScanLevel,
-1);//-1 flag is slower but ensures correct results
} else if (op == SpatialOperation.Contains) {
return new ContainsPrefixTreeFilter(shape, getFieldName(), grid, detailLevel);
}
throw new UnsupportedSpatialOperation(op);
}
}