org.apache.lucene.spatial.util.DistanceToShapeValueSource.java Source code

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Here is the source code for org.apache.lucene.spatial.util.DistanceToShapeValueSource.java

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/*
 * 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.
 */
package org.apache.lucene.spatial.util;

import java.io.IOException;

import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.search.DoubleValues;
import org.apache.lucene.search.DoubleValuesSource;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.spatial.ShapeValues;
import org.apache.lucene.spatial.ShapeValuesSource;
import org.locationtech.spatial4j.context.SpatialContext;
import org.locationtech.spatial4j.distance.DistanceCalculator;
import org.locationtech.spatial4j.shape.Point;

/**
 * The distance from a provided Point to a Point retrieved from an ShapeValuesSource. The distance
 * is calculated via a {@link org.locationtech.spatial4j.distance.DistanceCalculator}.
 *
 * @lucene.experimental
 */
public class DistanceToShapeValueSource extends DoubleValuesSource {

    private final ShapeValuesSource shapeValueSource;
    private final Point queryPoint;
    private final double multiplier;
    private final DistanceCalculator distCalc;

    //TODO if DoubleValues returns NaN; will things be ok?
    private final double nullValue;

    public DistanceToShapeValueSource(ShapeValuesSource 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 toString() {
        return "distance(" + queryPoint + " to " + shapeValueSource.toString() + ")*" + multiplier + ")";
    }

    @Override
    public DoubleValues getValues(LeafReaderContext readerContext, DoubleValues scores) throws IOException {

        final ShapeValues shapeValues = shapeValueSource.getValues(readerContext);

        return DoubleValues.withDefault(new DoubleValues() {
            @Override
            public double doubleValue() throws IOException {
                return distCalc.distance(queryPoint, shapeValues.value().getCenter()) * multiplier;
            }

            @Override
            public boolean advanceExact(int doc) throws IOException {
                return shapeValues.advanceExact(doc);
            }
        }, nullValue);
    }

    @Override
    public boolean needsScores() {
        return false;
    }

    @Override
    public boolean isCacheable(LeafReaderContext ctx) {
        return shapeValueSource.isCacheable(ctx);
    }

    @Override
    public DoubleValuesSource rewrite(IndexSearcher searcher) throws IOException {
        return this;
    }

    @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;
    }
}