package org.apache.lucene.spatial.vector;
/*
* 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.distance.DistanceCalculator;
import com.spatial4j.core.shape.Point;
import org.apache.lucene.index.AtomicReader;
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.queries.function.FunctionValues;
import org.apache.lucene.queries.function.ValueSource;
import org.apache.lucene.search.FieldCache;
import org.apache.lucene.util.Bits;
import java.io.IOException;
import java.util.Map;
/**
* An implementation of the Lucene ValueSource model that returns the distance
* for a {@link PointVectorStrategy}.
*
* @lucene.internal
*/
public class DistanceValueSource extends ValueSource {
private PointVectorStrategy strategy;
private final Point from;
/**
* Constructor.
*/
public DistanceValueSource(PointVectorStrategy strategy, Point from) {
this.strategy = strategy;
this.from = from;
}
/**
* Returns the ValueSource description.
*/
@Override
public String description() {
return "DistanceValueSource("+strategy+", "+from+")";
}
/**
* Returns the FunctionValues used by the function query.
*/
@Override
public FunctionValues getValues(Map context, AtomicReaderContext readerContext) throws IOException {
AtomicReader reader = readerContext.reader();
final FieldCache.Doubles ptX = FieldCache.DEFAULT.getDoubles(reader, strategy.getFieldNameX(), true);
final FieldCache.Doubles ptY = FieldCache.DEFAULT.getDoubles(reader, strategy.getFieldNameY(), true);
final Bits validX = FieldCache.DEFAULT.getDocsWithField(reader, strategy.getFieldNameX());
final Bits validY = FieldCache.DEFAULT.getDocsWithField(reader, strategy.getFieldNameY());
return new FunctionValues() {
private final Point from = DistanceValueSource.this.from;
private final DistanceCalculator calculator = strategy.getSpatialContext().getDistCalc();
private final double nullValue = (strategy.getSpatialContext().isGeo() ? 180 : Double.MAX_VALUE);
@Override
public float floatVal(int doc) {
return (float) doubleVal(doc);
}
@Override
public double doubleVal(int doc) {
// make sure it has minX and area
if (validX.get(doc)) {
assert validY.get(doc);
return calculator.distance(from, ptX.get(doc), ptY.get(doc));
}
return nullValue;
}
@Override
public String toString(int doc) {
return description() + "=" + floatVal(doc);
}
};
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
DistanceValueSource that = (DistanceValueSource) o;
if (!from.equals(that.from)) return false;
if (!strategy.equals(that.strategy)) return false;
return true;
}
@Override
public int hashCode() {
return from.hashCode();
}
}