package org.apache.lucene.spatial.util;
/*
* 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.context.SpatialContext;
import com.spatial4j.core.distance.DistanceCalculator;
import com.spatial4j.core.shape.Point;
import com.spatial4j.core.shape.Shape;
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.queries.function.FunctionValues;
import org.apache.lucene.queries.function.ValueSource;
import org.apache.lucene.queries.function.docvalues.DoubleDocValues;
import org.apache.lucene.search.Explanation;
import org.apache.lucene.search.IndexSearcher;
import java.io.IOException;
import java.util.Map;
/**
* The distance from a provided Point to a Point retrieved from a ValueSource via
* {@link org.apache.lucene.queries.function.FunctionValues#objectVal(int)}. The distance
* is calculated via a {@link com.spatial4j.core.distance.DistanceCalculator}.
*
* @lucene.experimental
*/
public class DistanceToShapeValueSource extends ValueSource {
private final ValueSource shapeValueSource;
private final Point queryPoint;
private final double multiplier;
private final DistanceCalculator distCalc;
//TODO if FunctionValues returns NaN; will things be ok?
private final double nullValue;//computed
public DistanceToShapeValueSource(ValueSource shapeValueSource, Point queryPoint,
double multiplier, SpatialContext ctx) {
this.shapeValueSource = shapeValueSource;
this.queryPoint = queryPoint;
this.multiplier = multiplier;
this.distCalc = ctx.getDistCalc();
this.nullValue =
(ctx.isGeo() ? 180 * multiplier : Double.MAX_VALUE);
}
@Override
public String description() {
return "distance(" + queryPoint + " to " + shapeValueSource.description() + ")*" + multiplier + ")";
}
@Override
public void createWeight(Map context, IndexSearcher searcher) throws IOException {
shapeValueSource.createWeight(context, searcher);
}
@Override
public FunctionValues getValues(Map context, AtomicReaderContext readerContext) throws IOException {
final FunctionValues shapeValues = shapeValueSource.getValues(context, readerContext);
return new DoubleDocValues(this) {
@Override
public double doubleVal(int doc) {
Shape shape = (Shape) shapeValues.objectVal(doc);
if (shape == null || shape.isEmpty())
return nullValue;
Point pt = shape.getCenter();
return distCalc.distance(queryPoint, pt) * multiplier;
}
@Override
public Explanation explain(int doc) {
Explanation exp = super.explain(doc);
exp.addDetail(shapeValues.explain(doc));
return exp;
}
};
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
DistanceToShapeValueSource that = (DistanceToShapeValueSource) o;
if (!queryPoint.equals(that.queryPoint)) return false;
if (Double.compare(that.multiplier, multiplier) != 0) return false;
if (!shapeValueSource.equals(that.shapeValueSource)) return false;
if (!distCalc.equals(that.distCalc)) return false;
return true;
}
@Override
public int hashCode() {
int result;
long temp;
result = shapeValueSource.hashCode();
result = 31 * result + queryPoint.hashCode();
temp = Double.doubleToLongBits(multiplier);
result = 31 * result + (int) (temp ^ (temp >>> 32));
return result;
}
}