/*
* 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.demo.facet;
import java.io.Closeable;
import java.io.IOException;
import java.text.ParseException;
import org.apache.lucene.analysis.core.WhitespaceAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.DoublePoint;
import org.apache.lucene.document.NumericDocValuesField;
import org.apache.lucene.expressions.Expression;
import org.apache.lucene.expressions.SimpleBindings;
import org.apache.lucene.expressions.js.JavascriptCompiler;
import org.apache.lucene.facet.DrillDownQuery;
import org.apache.lucene.facet.DrillSideways;
import org.apache.lucene.facet.FacetResult;
import org.apache.lucene.facet.Facets;
import org.apache.lucene.facet.FacetsCollector;
import org.apache.lucene.facet.FacetsConfig;
import org.apache.lucene.facet.range.DoubleRange;
import org.apache.lucene.facet.range.DoubleRangeFacetCounts;
import org.apache.lucene.facet.taxonomy.TaxonomyReader;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.DoubleValuesSource;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.MatchAllDocsQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.SortField;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.SloppyMath;
/** Shows simple usage of dynamic range faceting, using the
* expressions module to calculate distance. */
public class DistanceFacetsExample implements Closeable {
final DoubleRange ONE_KM = new DoubleRange("< 1 km", 0.0, true, 1.0, false);
final DoubleRange TWO_KM = new DoubleRange("< 2 km", 0.0, true, 2.0, false);
final DoubleRange FIVE_KM = new DoubleRange("< 5 km", 0.0, true, 5.0, false);
final DoubleRange TEN_KM = new DoubleRange("< 10 km", 0.0, true, 10.0, false);
private final Directory indexDir = new RAMDirectory();
private IndexSearcher searcher;
private final FacetsConfig config = new FacetsConfig();
/** The "home" latitude. */
public final static double ORIGIN_LATITUDE = 40.7143528;
/** The "home" longitude. */
public final static double ORIGIN_LONGITUDE = -74.0059731;
/** Mean radius of the Earth in KM
*
* NOTE: this is approximate, because the earth is a bit
* wider at the equator than the poles. See
* http://en.wikipedia.org/wiki/Earth_radius */
// see http://earth-info.nga.mil/GandG/publications/tr8350.2/wgs84fin.pdf
public final static double EARTH_RADIUS_KM = 6_371.0087714;
/** Empty constructor */
public DistanceFacetsExample() {}
/** Build the example index. */
public void index() throws IOException {
IndexWriter writer = new IndexWriter(indexDir, new IndexWriterConfig(
new WhitespaceAnalyzer()).setOpenMode(OpenMode.CREATE));
// TODO: we could index in radians instead ... saves all the conversions in getBoundingBoxFilter
// Add documents with latitude/longitude location:
// we index these both as DoublePoints (for bounding box/ranges) and as NumericDocValuesFields (for scoring)
Document doc = new Document();
doc.add(new DoublePoint("latitude", 40.759011));
doc.add(new NumericDocValuesField("latitude", Double.doubleToRawLongBits(40.759011)));
doc.add(new DoublePoint("longitude", -73.9844722));
doc.add(new NumericDocValuesField("longitude", Double.doubleToRawLongBits(-73.9844722)));
writer.addDocument(doc);
doc = new Document();
doc.add(new DoublePoint("latitude", 40.718266));
doc.add(new NumericDocValuesField("latitude", Double.doubleToRawLongBits(40.718266)));
doc.add(new DoublePoint("longitude", -74.007819));
doc.add(new NumericDocValuesField("longitude", Double.doubleToRawLongBits(-74.007819)));
writer.addDocument(doc);
doc = new Document();
doc.add(new DoublePoint("latitude", 40.7051157));
doc.add(new NumericDocValuesField("latitude", Double.doubleToRawLongBits(40.7051157)));
doc.add(new DoublePoint("longitude", -74.0088305));
doc.add(new NumericDocValuesField("longitude", Double.doubleToRawLongBits(-74.0088305)));
writer.addDocument(doc);
// Open near-real-time searcher
searcher = new IndexSearcher(DirectoryReader.open(writer));
writer.close();
}
private DoubleValuesSource getDistanceValueSource() {
Expression distance;
try {
distance = JavascriptCompiler.compile(
"haversin(" + ORIGIN_LATITUDE + "," + ORIGIN_LONGITUDE + ",latitude,longitude)");
} catch (ParseException pe) {
// Should not happen
throw new RuntimeException(pe);
}
SimpleBindings bindings = new SimpleBindings();
bindings.add(new SortField("latitude", SortField.Type.DOUBLE));
bindings.add(new SortField("longitude", SortField.Type.DOUBLE));
return distance.getDoubleValuesSource(bindings);
}
/** Given a latitude and longitude (in degrees) and the
* maximum great circle (surface of the earth) distance,
* returns a simple Filter bounding box to "fast match"
* candidates. */
public static Query getBoundingBoxQuery(double originLat, double originLng, double maxDistanceKM) {
// Basic bounding box geo math from
// http://JanMatuschek.de/LatitudeLongitudeBoundingCoordinates,
// licensed under creative commons 3.0:
// http://creativecommons.org/licenses/by/3.0
// TODO: maybe switch to recursive prefix tree instead
// (in lucene/spatial)? It should be more efficient
// since it's a 2D trie...
// Degrees -> Radians:
double originLatRadians = SloppyMath.toRadians(originLat);
double originLngRadians = SloppyMath.toRadians(originLng);
double angle = maxDistanceKM / EARTH_RADIUS_KM;
double minLat = originLatRadians - angle;
double maxLat = originLatRadians + angle;
double minLng;
double maxLng;
if (minLat > SloppyMath.toRadians(-90) && maxLat < SloppyMath.toRadians(90)) {
double delta = Math.asin(Math.sin(angle)/Math.cos(originLatRadians));
minLng = originLngRadians - delta;
if (minLng < SloppyMath.toRadians(-180)) {
minLng += 2 * Math.PI;
}
maxLng = originLngRadians + delta;
if (maxLng > SloppyMath.toRadians(180)) {
maxLng -= 2 * Math.PI;
}
} else {
// The query includes a pole!
minLat = Math.max(minLat, SloppyMath.toRadians(-90));
maxLat = Math.min(maxLat, SloppyMath.toRadians(90));
minLng = SloppyMath.toRadians(-180);
maxLng = SloppyMath.toRadians(180);
}
BooleanQuery.Builder f = new BooleanQuery.Builder();
// Add latitude range filter:
f.add(DoublePoint.newRangeQuery("latitude", SloppyMath.toDegrees(minLat), SloppyMath.toDegrees(maxLat)),
BooleanClause.Occur.FILTER);
// Add longitude range filter:
if (minLng > maxLng) {
// The bounding box crosses the international date
// line:
BooleanQuery.Builder lonF = new BooleanQuery.Builder();
lonF.add(DoublePoint.newRangeQuery("longitude", SloppyMath.toDegrees(minLng), Double.POSITIVE_INFINITY),
BooleanClause.Occur.SHOULD);
lonF.add(DoublePoint.newRangeQuery("longitude", Double.NEGATIVE_INFINITY, SloppyMath.toDegrees(maxLng)),
BooleanClause.Occur.SHOULD);
f.add(lonF.build(), BooleanClause.Occur.MUST);
} else {
f.add(DoublePoint.newRangeQuery("longitude", SloppyMath.toDegrees(minLng), SloppyMath.toDegrees(maxLng)),
BooleanClause.Occur.FILTER);
}
return f.build();
}
/** User runs a query and counts facets. */
public FacetResult search() throws IOException {
FacetsCollector fc = new FacetsCollector();
searcher.search(new MatchAllDocsQuery(), fc);
Facets facets = new DoubleRangeFacetCounts("field", getDistanceValueSource(), fc,
getBoundingBoxQuery(ORIGIN_LATITUDE, ORIGIN_LONGITUDE, 10.0),
ONE_KM,
TWO_KM,
FIVE_KM,
TEN_KM);
return facets.getTopChildren(10, "field");
}
/** User drills down on the specified range. */
public TopDocs drillDown(DoubleRange range) throws IOException {
// Passing no baseQuery means we drill down on all
// documents ("browse only"):
DrillDownQuery q = new DrillDownQuery(null);
final DoubleValuesSource vs = getDistanceValueSource();
q.add("field", range.getQuery(getBoundingBoxQuery(ORIGIN_LATITUDE, ORIGIN_LONGITUDE, range.max), vs));
DrillSideways ds = new DrillSideways(searcher, config, (TaxonomyReader) null) {
@Override
protected Facets buildFacetsResult(FacetsCollector drillDowns, FacetsCollector[] drillSideways, String[] drillSidewaysDims) throws IOException {
assert drillSideways.length == 1;
return new DoubleRangeFacetCounts("field", vs, drillSideways[0], ONE_KM, TWO_KM, FIVE_KM, TEN_KM);
}
};
return ds.search(q, 10).hits;
}
@Override
public void close() throws IOException {
searcher.getIndexReader().close();
indexDir.close();
}
/** Runs the search and drill-down examples and prints the results. */
public static void main(String[] args) throws Exception {
DistanceFacetsExample example = new DistanceFacetsExample();
example.index();
System.out.println("Distance facet counting example:");
System.out.println("-----------------------");
System.out.println(example.search());
System.out.println("Distance facet drill-down example (field/< 2 km):");
System.out.println("---------------------------------------------");
TopDocs hits = example.drillDown(example.TWO_KM);
System.out.println(hits.totalHits + " totalHits");
example.close();
}
}