Implementing Geospatial Bounding Box Search in Lucene 4.x

In my last blog post i explained about Geospatial Radial Search using Lucene 4.x.
In continuation with this i am going to explain how to implement GeoSpatial Bounding Box Search using Lucene 4.x.

Problem I am trying to Implement :

Finding All Places Within Given Bounding Box.

Sample Input Places Data :

id  name             latitude   longitude
       
        //Bangalore places
1   Bangalore        12.9558    77.620979
        2   Cubbon Park      12.974045  77.591995      
        3   Tipu Palace      12.959365  77.573792
        4   Bangalore Palace 12.998095  77.592041
        5   Monkey Bar       12.97018   77.61219

        //Chennai places
        6   Chennai    13.060422    80.249583
        7   Elliot's Beach    12.998976    80.271286
        8   Kapaleeshwar Temple    13.033889    80.269722

Code :

import java.io.File;

import java.io.IOException;

import org.apache.lucene.analysis.standard.StandardAnalyzer;

import org.apache.lucene.document.Document;

import org.apache.lucene.document.Field;

import org.apache.lucene.document.Field.Store;

import org.apache.lucene.document.FieldType;

import org.apache.lucene.document.IntField;

import org.apache.lucene.document.StoredField;

import org.apache.lucene.index.DirectoryReader;

import org.apache.lucene.index.IndexReader;

import org.apache.lucene.index.IndexWriter;

import org.apache.lucene.index.IndexWriterConfig;

import org.apache.lucene.index.IndexableField;

import org.apache.lucene.queries.function.ValueSource;

import org.apache.lucene.search.Filter;

import org.apache.lucene.search.IndexSearcher;

import org.apache.lucene.search.MatchAllDocsQuery;

import org.apache.lucene.search.ScoreDoc;

import org.apache.lucene.search.Sort;

import org.apache.lucene.search.TopDocs;

import org.apache.lucene.spatial.SpatialStrategy;

import org.apache.lucene.spatial.prefix.RecursivePrefixTreeStrategy;

import org.apache.lucene.spatial.prefix.tree.GeohashPrefixTree;

import org.apache.lucene.spatial.prefix.tree.SpatialPrefixTree;

import org.apache.lucene.spatial.query.SpatialArgs;

import org.apache.lucene.spatial.query.SpatialOperation;

import org.apache.lucene.store.Directory;

import org.apache.lucene.store.SimpleFSDirectory;

import org.apache.lucene.util.Version;

import com.spatial4j.core.context.SpatialContext;

import com.spatial4j.core.distance.DistanceUtils;

import com.spatial4j.core.shape.Point;

import com.spatial4j.core.shape.Shape;

public class SpatialSearch {

private IndexWriter indexWriter;

private IndexReader indexReader;

private IndexSearcher searcher;

private SpatialContext ctx;

private SpatialStrategy strategy;

public SpatialSearch(String indexPath) {

StandardAnalyzer a = new StandardAnalyzer(Version.LUCENE_43);

IndexWriterConfig iwc = new IndexWriterConfig(Version.LUCENE_43, a);

Directory directory;

try {

directory = new SimpleFSDirectory(new File(indexPath));

indexWriter = new IndexWriter(directory, iwc);

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

this.ctx = SpatialContext.GEO;

SpatialPrefixTree grid = new GeohashPrefixTree(ctx, 11);

this.strategy = new RecursivePrefixTreeStrategy(grid, "location");

}

public void indexDocuments() throws IOException {

indexWriter.addDocument(newGeoDocument(1, "Bangalore", ctx.makePoint(12.9558, 77.620979)));

indexWriter.addDocument(newGeoDocument(2, "Cubbon Park", ctx.makePoint(12.974045, 77.591995)));

indexWriter.addDocument(newGeoDocument(3, "Tipu palace", ctx.makePoint(12.959365, 77.573792)));

indexWriter.addDocument(newGeoDocument(4, "Bangalore palace", ctx.makePoint(12.998095, 77.592041)));

indexWriter.addDocument(newGeoDocument(5, "Monkey Bar", ctx.makePoint(12.97018, 77.61219)));

indexWriter.addDocument(newGeoDocument(6, "Chennai", ctx.makePoint(13.060422, 80.249583)));

 indexWriter.addDocument(newGeoDocument(7, "Elliot's Beach", ctx.makePoint(12.998976, 80.271286))); 

 indexWriter.addDocument(newGeoDocument(8, "Kapaleeshwar Temple", ctx.makePoint(13.033889, 80.269722)));

indexWriter.commit();

indexWriter.close();

}

private Document newGeoDocument(int id, String name, Shape shape) {

FieldType ft = new FieldType();

ft.setIndexed(true);

ft.setStored(true);

Document doc = new Document();

doc.add(new IntField("id", id, Store.YES));

doc.add(new Field("name", name, ft));

for(IndexableField f:strategy.createIndexableFields(shape)) {

doc.add(f);

}

doc.add(new StoredField(strategy.getFieldName(), ctx.toString(shape)));

return doc;

}

public void setSearchIndexPath(String indexPath) throws IOException{

this.indexReader = DirectoryReader.open(new SimpleFSDirectory(new File(indexPath)));

this.searcher = new IndexSearcher(indexReader);

}

public void searchBBox(Double minLat, Double minLng, Double maxLat, Double maxLng) throws IOException {

   SpatialArgs args = new SpatialArgs(SpatialOperation.IsWithin, ctx.makeRectangle(minLat, maxLat, minLng, maxLng));

   Filter filter = strategy.makeFilter(args);

   int limit = 10; 

   TopDocs topDocs = searcher.search(new MatchAllDocsQuery(), filter, limit);

   ScoreDoc[] scoreDocs = topDocs.scoreDocs; 

   for (ScoreDoc s : scoreDocs) { 

       Document doc = searcher.doc(s.doc); 

       System.out.println(doc.get("id") + "\t" + doc.get("name")); 

   } 

 }

 

}

/**

 * @param args

 * @throws IOException 

 */

public static void main(String[] args) throws IOException {

// TODO Auto-generated method stub

String indexPath = "/home/vishnu/lucene_practices/geo_spatial_index";

SpatialSearch s = new SpatialSearch(indexPath);

//Indexes sample documents

s.indexDocuments();

s.setSearchIndexPath(indexPath);

//Get Places Within Chennai Bounding Box. 

 System.out.println("Places WithIn Chennai Bounding Box\n"); 

 s.searchBBox(12.9673, 80.184631, 13.15148, 80.306709); 

 //Get Places Within Bangalore Bounding Box.

 System.out.println("Places WithIn Bangalore Bounding Box"); 

 s.searchBBox(12.76805, 77.465202, 13.14355, 77.776749);

}

}

Output :

Places WithIn Chennai Bounding Box
6 Chennai
7 Elliot's Beach
8 Kapaleeshwar Temple

Places WithIn Bangalore Bounding Box
1 Bangalore
2 Cubbon Park
3 Tipu palace
4 Bangalore palace
5 Monkey Bar