package org.apache.solr.search.function.distance;
/**
* 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 org.apache.solr.search.function.ValueSource;
import org.apache.solr.search.function.DocValues;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.spatial.geohash.GeoHashUtils;
import java.util.Map;
import java.io.IOException;
/**
* Takes in a latitude and longitude ValueSource and produces a GeoHash.
* <p/>
* Ex: geohash(lat, lon)
*
* <p/>
* Note, there is no reciprocal function for this.
**/
public class GeohashFunction extends ValueSource {
protected ValueSource lat, lon;
public GeohashFunction(ValueSource lat, ValueSource lon) {
this.lat = lat;
this.lon = lon;
}
protected String name() {
return "geohash";
}
@Override
public DocValues getValues(Map context, IndexReader reader) throws IOException {
final DocValues latDV = lat.getValues(context, reader);
final DocValues lonDV = lon.getValues(context, reader);
return new DocValues() {
@Override
public String strVal(int doc) {
return GeoHashUtils.encode(latDV.doubleVal(doc), lonDV.doubleVal(doc));
}
@Override
public String toString(int doc) {
StringBuilder sb = new StringBuilder();
sb.append(name()).append('(');
sb.append(latDV.toString(doc)).append(',').append(lonDV.toString(doc));
sb.append(')');
return sb.toString();
}
};
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof GeohashFunction)) return false;
GeohashFunction that = (GeohashFunction) o;
if (!lat.equals(that.lat)) return false;
if (!lon.equals(that.lon)) return false;
return true;
}
@Override
public int hashCode() {
int result = lat.hashCode();
result = 29 * result - lon.hashCode();
return result;
}
@Override
public String description() {
StringBuilder sb = new StringBuilder();
sb.append(name()).append('(');
sb.append(lat).append(',').append(lon);
sb.append(')');
return sb.toString();
}
}