Lucene 5.5.3具有递归前缀树策略的空间索引

Question

I would like to spatially index shapes to support polygon and point based queries. However, I am having a hard time creating the lucene document needed for this. The idea is to use a recursive prefix tree to do a quick filtering of shapes based on the geohash, then do a granular filter by checking the serialization of the shape to see if the queried polygon does indeed match ( explained here ).

The first problem I have is the inability to create the indexable fields to be added to the spatial document:

Document doc = new Document();
Field[] fields = rptStrategy.createIndexableFields(spatial4jShape.getBoundingBox());
for (Field f : fields) {
  doc.add(f);
}

The second problem I run into is not being able to use a Jts shape for the serialization part:

fields = dvStrategy.createIndexableFields((Shape)spatial4jShape);

That throws an IllegalArgumentException java.lang.IllegalArgumentException: Unsupported shape class com.spatial4j.core.shape.jts.JtsGeometry

My question is now

1. What am I doing wrong with the Recursive prefix tree?
2. How do I use the serialized strategy to index the polygon itself?

Full Code:

import com.spatial4j.core.context.SpatialContext;
import com.spatial4j.core.context.jts.JtsSpatialContext;
import com.spatial4j.core.io.jts.JtsWKTReader;
import com.spatial4j.core.shape.Shape;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexableField;
import org.apache.lucene.spatial.prefix.RecursivePrefixTreeStrategy;
import org.apache.lucene.spatial.prefix.tree.GeohashPrefixTree;
import org.apache.lucene.spatial.serialized.SerializedDVStrategy;

import java.text.ParseException;

public class TestLuceneSpatial {
  public static void main(String[] args) throws ParseException {
    String wkt = "POLYGON((-122.4604 37.7818,-122.4707 37.7645,-122.4659 37.7509,-122.4337 37.7476,-122.4192 37.7856,-122.4604 37.7818))";
    SpatialContext ctx = SpatialContext.GEO;
    GeohashPrefixTree grid = new GeohashPrefixTree(ctx, 6);
    RecursivePrefixTreeStrategy rptStrategy = new RecursivePrefixTreeStrategy(grid, "rptBBox");
    rptStrategy.setPrefixGridScanLevel(grid.getMaxLevels() - 1);
    SerializedDVStrategy dvStrategy = new SerializedDVStrategy(ctx, "polygon");

    JtsWKTReader wktReader = new JtsWKTReader(JtsSpatialContext.GEO, null);
    Shape spatial4jShape = wktReader.parse(wkt);

    Document doc = new Document();
    Field[] fields = rptStrategy.createIndexableFields(spatial4jShape.getBoundingBox());
    for (Field f : fields) {
      doc.add(f);
    }

    fields = dvStrategy.createIndexableFields((Shape)spatial4jShape);
    for (Field f : fields) {
      doc.add(f);
    }

    for (IndexableField f : doc.getFields()) {
      System.out.printf("%s => %s\n", f.name(), f.binaryValue());
    }

    System.out.println(doc);

  }
}

Answer 1

Too late but may help

 private val ctx = new JtsSpatialContextFactory().newSpatialContext

and use shape directly

Field[] fields = rptStrategy.createIndexableFields(spatial4jShape);