Support/Doc | About | Purchase | Advanced Search
AGGeospatialPolygons.java

package com.franz.agbase.examples;



import com.franz.agbase.*;



public class AGGeospatialPolygons {



    /**

     * Demonstrates some basics of working with Polygons.

     * 

     * @param args unused

     * @throws AllegroGraphException

     */

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

        // Connect to server, which must already be running.

        AllegroGraphConnection ags = new AllegroGraphConnection();

        try {

            ags.enable();

        } catch (Exception e) {

            throw new AllegroGraphException("Server connection problem", e);

        }



        // Create a fresh triple-store.

        AllegroGraph ts = ags.renew("geospatialpolygons", AGPaths.TRIPLE_STORES);

        

        // Register namespaces

        ts.registerNamespace("ex","http://example.org/");

        

        // Get a GeoExtension instance for this store to work with geospatial features 

        GeoExtension geo = ts.getGeoExtension();

        

        // Define a geospatial subtype to encode coordinates 

        GeospatialSubtype subtype = geo.registerCartesianStriping(0,10,0,10,.1);

        geo.addSubtype(subtype);

        

        // Define a 4-sided polygon

        Polygon p1 = new Polygon(4);

        p1.setSubject(ts.addPart("!ex:p1").queryAGId());

        p1.addVertex(0,0);

        p1.addVertex(0,10);

        p1.addVertex(6,6);

        p1.addVertex(10,0);

        p1.setSubtype(subtype);

        p1.add(ts);

        

        // Define another 4-sided polygon

        Polygon p2 = new Polygon(4);

        p2.setSubject(ts.addPart("!ex:p2").queryAGId());

        p2.addVertex(0,0);

        p2.addVertex(0,10);

        p2.addVertex(4,4);

        p2.addVertex(10,0);

        p2.setSubtype(subtype);

        p2.add(ts);

        

        // Define an 8-sided polygon

        Polygon p3 = new Polygon(8);

        p3.setSubject(ts.addPart("!ex:p3").queryAGId());

        p3.addVertex(0,0);

        p3.addVertex(0,10);

        p3.addVertex(10,10);

        p3.addVertex(6,6);

        p3.addVertex(4,6);

        p3.addVertex(4,4);

        p3.addVertex(6,4);

        p3.addVertex(0,10);

        p3.setSubtype(subtype);

        p3.add(ts);

        

        // Index the store

        AGIndexAllTriples.indexAllTriplesWithTiming(ts);

        

        // Show all triples in the store

        TriplesIterator cc = ts.getStatements(null,null,null);

        AGUtils.showTriples("All triples:",cc);

        

        // Query to determine whether a point is inside the polygons

        System.out.println("Is the point (5,5) inside p1? " + p1.pointInside(5,5));

        System.out.println("Is the point (5,5) inside p2? " + p2.pointInside(5,5));

        System.out.println("Is the point (5,5) inside p3? " + p3.pointInside(5,5));

        System.out.println("Is the point (0.5,0.5) inside p3? " + p3.pointInside(0.5,0.5));

        

        // Close the store and disconnect from the server.

        ts.closeTripleStore();

        ags.disable();

    }

}
Up | Next