Hi, all

I was trying to add some distance search capabilities to an index using spatial 
lucene in lucene 3.0 but could not get it working. So I wrote a very small test 
example to try out the api. However, even the simplest test case would NOT 
function correctly either.

Anyone has ideas/experiences about spatial lucene in 3.0?

My codes

//tested using core-3.0, misc-3.0, spatial-3.0, the following code snippet does 
not return any results but it should

import java.io.IOException;

import org.apache.lucene.analysis.WhitespaceAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.Field.Index;
import org.apache.lucene.document.Field.Store;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.IndexWriter.MaxFieldLength;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.spatial.tier.DistanceQueryBuilder;
import org.apache.lucene.spatial.tier.projections.CartesianTierPlotter;
import org.apache.lucene.spatial.tier.projections.IProjector;
import org.apache.lucene.spatial.tier.projections.SinusoidalProjector;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.NumericUtils;

public class SpatialLuceneExample{
    private static final String LAT_FIELD = "lat", LON_FIELD = "lon", 
TIER_PREFIX_FIELD = "_localTier";

    private double maxMiles = 25, minMiles = 1; // anything lower than 1 mile 
will just give tier 15
    // see 
http://www.nsshutdown.com/projects/lucene/whitepaper/locallucene_v2.html
    private IProjector projector = new SinusoidalProjector();
    private CartesianTierPlotter ctp = new CartesianTierPlotter(0, projector, 
TIER_PREFIX_FIELD);
    //startTier is 14 for 25 miles, 15 for 1 miles in lucene 3.0
    private int startTier = 5, endTier = 15;

    /**
     * Add the lat, lon, and tier box id to the document
     * see 
http://www.nsshutdown.com/projects/lucene/whitepaper/locallucene_v2.html
     * @param lat
     * @param lon
     * @param document a geo document
     */
    private void addSpatialLcnFields(double lat, double lon, Document document){
        document.add(new Field(LAT_FIELD, 
NumericUtils.doubleToPrefixCoded(lat), Field.Store.YES, 
Field.Index.NOT_ANALYZED));
        document.add(new Field(LON_FIELD, 
NumericUtils.doubleToPrefixCoded(lon), Field.Store.YES, 
Field.Index.NOT_ANALYZED));

        for(int tier = startTier ; tier<= endTier; tier++){
            CartesianTierPlotter ctp = new CartesianTierPlotter(tier, 
projector, TIER_PREFIX_FIELD);
            double boxId = ctp.getTierBoxId(lat, lon);
            document.add(new Field(ctp.getTierFieldName(), 
NumericUtils.doubleToPrefixCoded(boxId), Field.Store.YES, 
Field.Index.NOT_ANALYZED_NO_NORMS));
        }
    }


    private void addLocation(IndexWriter writer, String name, double lat, 
double lon) throws IOException{
      Document doc = new Document();
      doc.add(new Field("name", name, Field.Store.YES, Index.ANALYZED));
      doc.add(new Field("metafile", "doc", Store.YES, Index.ANALYZED));
      addSpatialLcnFields(lat, lon, doc);
      writer.addDocument(doc);
    }

      public static void main(String[] args) throws Exception{
            SpatialLuceneExample sle = new SpatialLuceneExample();
            Directory dir = new RAMDirectory();
            IndexWriter writer = new IndexWriter(dir, new WhitespaceAnalyzer(), 
MaxFieldLength.UNLIMITED);

            sle.addLocation(writer, "test", 39.9260, -75.1566);

            writer.commit();
            writer.close();

            IndexSearcher searcher = new IndexSearcher(dir);
            DistanceQueryBuilder dq = new DistanceQueryBuilder(39.9260, 
-75.1566, 10d, LAT_FIELD, LON_FIELD, true);

            Query tq = new TermQuery(new Term("metafile", "doc"));
            TopDocs hits = searcher.search(tq, dq.getFilter(), 10);
            for(int i =0; i<hits.totalHits; i++){
                  Document doc = searcher.doc(hits.scoreDocs[i].doc);
                  System.out.println(doc.get("name"));
            }
      }
}

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