MongoDB for Java and geospatial space Operations

A 2d Sphere Index supports queries that calculate geometries on A earth-like sphere. The index supports data stored as both Geojson objects and as legacy coordinate. The index supports legacy coordinate pairs by converting the ' data to the ' Geojson point type.
Translation: 2d sphere index supports spherical geometry query. Data storage is dominated by Geojson objects.

Store your location data as Geojson objects with this coordinate-axis order:longitude, latitude. The coordinate reference system for Geojson uses the WGS84 datum.

/** * Convert to Geojson object/public String Getgeojson (String lon,string lat) throws jsonexception{
        Jsonobject point = new Jsonobject ();
        Point.put ("type", "point");
        Jsonarray coord = new Jsonarray ("[" +lon+ "," +lat+ "]");
        Point.put ("coordinates", coord);
      return point.tostring (); /** * Insert space Data * @param collection * @throws jsonexception/public void I Nsert (Dbcollection collection) throws jsonexception{dbobject point1 = new Basicdbobj
            ECT ();
            Point1.put ("name", "001");
            
            Point1.put ("Geo", Getgeojson ("116.342176", "39.995376"));
            DBObject Point2 = new Basicdbobject ();
            Point2.put ("name", "002");
            
            Point2.put ("Geo", Getgeojson ("116.348694", "39.990965"));
            DBObject point3 = new Basicdbobject ();
            Point3.put ("Name", "003");Point3.put ("Geo", Getgeojson ("116.343318", "39.991184"));
            DBObject point4 = new Basicdbobject ();
            Point4.put ("name", "004");
            Point4.put ("Geo", Getgeojson ("116.359590", "39.982762"));
            list<dbobject> list = new arraylist<dbobject> ();
            List.add (POINT1);
            List.add (Point2);
            List.add (POINT3);
            List.add (POINT4);
      Collection.insert (list). GETN (); /** * Create spatial Index * @param collection */public void Makespatialindexs (Dbcollection c
      ollection) {Collection.ensureindex (New Basicdbobject ("Geo", "2dsphere"), "Geospatialidx"); /** * All elements within the query rectangle * @param collection/public void query Dbcollection Collectio
            N) {list<double[]> box = new arraylist<double[]> (); Box.add (new double[] {116.341795,39.992277}); Top left corner coordinate BoX.add (New double[]{116.350122,39.989251}); Lower right corner coordinate basicdbobject query = new Basicdbobject ("Loc", New Basicdbobject ("$within", New BASICDBOBJEC
            T ("$box", Box));
             Dbcursor cur1 = collection.find (query);
                  while (Cur1.hasnext ()) {Basicdbobject o = (basicdbobject) cur1.next (); System.
                  Out.println (O.get ("name")); System.
            Out.println (O.get ("geometry"));
 }
      }

More Space Operations Reference:
Http://java.dzone.com/articles/writing-geospatial-queries
References: geojson:http://www.geojson.org/geojson-spec.htmlgeospatial
Indexes and queries:http://docs.mongodb.org/manual/applications/geospatial-indexes/