| gvSIG desktop 1

/*

 * Created on 02-may-2006

 *

 * gvSIG. Sistema de Informaci?n Geogr?fica de la Generalitat Valenciana

 *

 * Copyright (C) 2004 IVER T.I. and Generalitat Valenciana.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 2

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,USA.

 *

 * For more information, contact:

 *

 *  Generalitat Valenciana

 *   Conselleria d'Infraestructures i Transport

 *   Av. Blasco Ib??ez, 50

 *   46010 VALENCIA

 *   SPAIN

 *

 *      +34 963862235

 *   gvsig@gva.es

 *      www.gvsig.gva.es

 *

 *    or

 *

 *   IVER T.I. S.A

 *   Salamanca 50

 *   46005 Valencia

 *   Spain

 *

 *   +34 963163400

 *   dac@iver.es

 */

/* CVS MESSAGES:

*

* $Id: SpatiallyIndexedSpatialJoinVisitor.java 5628 2006-06-02 18:21:28Z azabala $

* $Log$

* Revision 1.2  2006-06-02 18:21:28  azabala

* *** empty log message ***

*

* Revision 1.1  2006/05/24 21:09:47  azabala

* primera version en cvs despues de refactoring orientado a crear un framework extensible de geoprocessing

*

* Revision 1.1  2006/05/02 18:58:47  azabala

* first version in cvs

*

*

*/

package com.iver.cit.gvsig.geoprocess.spatialjoin.fmap;

import java.awt.geom.Rectangle2D;

import java.util.List;

import com.iver.cit.gvsig.fmap.DriverException;

import com.iver.cit.gvsig.fmap.core.IFeature;

import com.iver.cit.gvsig.fmap.core.IGeometry;

import com.iver.cit.gvsig.fmap.drivers.DriverIOException;

import com.iver.cit.gvsig.fmap.layers.FLyrVect;

import com.iver.cit.gvsig.fmap.layers.ReadableVectorial;

import com.iver.cit.gvsig.fmap.operations.strategies.VisitException;

import com.iver.cit.gvsig.fmap.spatialindex.INearestNeighbourFinder;

import com.iver.cit.gvsig.fmap.spatialindex.ISpatialIndex;

import com.iver.cit.gvsig.geoprocess.core.fmap.FeatureProcessor;

import com.vividsolutions.jts.geom.Geometry;

/**

 * This  visitor does spatial join with nearest neighbour 

 * criteria by using an spatial index with nearest neighbour

 * searching capabilities.<br>

 * By now, RTreeSptLib is the only spatial index that is also

 * a INearestNeigbourFinder implementation.

 * <br>

 * @author azabala

 *

 */

public class SpatiallyIndexedSpatialJoinVisitor extends

                NearestSpatialJoinVisitor {

        /**

         * Geometry.distance() is a costly operation. Thats the reason

         * for we are only using a nearest neighbour.

         * TODO SpatialIndex works with Rectangle2D, and this may be a simplification

         * that drives to errors. Make aditional probes to use a number of default

         * neighbours

         */

        static final int DEFAULT_NUM_NEIGBOURS = 1;

        /**

         * Number of neighbours that nearestFinder must

         * found.

         */

        int numOfNeighbours = DEFAULT_NUM_NEIGBOURS;

        /**

         * Spetialized instance in nearest neighbour searchs.

         */

        private INearestNeighbourFinder nearestFinder;

        /**

         * Constructor

         * @param sourceLayer

         * @param targetLayer

         * @param processor

         * @throws DriverException

         */

        public SpatiallyIndexedSpatialJoinVisitor(FLyrVect sourceLayer, 

                        FLyrVect targetLayer, 

                        FeatureProcessor processor) throws DriverException {

                super(sourceLayer, targetLayer, processor);

//                lo comentamos porque debe ser llamado externamente

//                initialize();

        }

        public void initialize(){

                ISpatialIndex spatialIndex =

                        targetLayer.getISpatialIndex();

                if(spatialIndex instanceof INearestNeighbourFinder)

                        nearestFinder = (INearestNeighbourFinder)spatialIndex;

                else

                        throw new IllegalArgumentException("La segunda capa de spatial join ha de tener un ?ndice espacial de tipo INearestNeighbourFinder para usar este visitor");

        }

        /**

         * Processes a Feature of source layer, looking for its nearest feature of

         * target layer and taking attributes from it

         */

        public void visit(IGeometry g, int sourceIndex) throws VisitException {

                if(g == null)

                        return;

                try {

long t0 = System.currentTimeMillis();                        

                //no se si el rtree har? la busqueda bien si el rectangulo

                //de busqueda no est? insertado. Hacer las pruebas (si no,

                //a?adimos ahora y borramos luego)

                Geometry gJts = g.toJTSGeometry();

                Rectangle2D rect = g.getBounds2D();        

                List nearestLst = nearestFinder.

                        findNNearest(numOfNeighbours, rect);

                int targetIndex = -1;//index of nearest neighbour

                double nearestDistance = Double.MAX_VALUE;

                ReadableVectorial rv = targetLayer.getSource();

                for(int i = 0; i < nearestLst.size(); i++){

                        int index2 = ((Integer)nearestLst.get(i)).intValue();

                        IGeometry g2 = rv.getShape(index2);

                        Geometry g2Jts = g2.toJTSGeometry();

                        double dist = gJts.distance(g2Jts);

                        if(dist <= nearestDistance){

                                //by adding <=, we follow the convention that

                                //if two features are at the same distance, take

                                //the last as nearest neighbour

                                nearestDistance = dist;

                                targetIndex = index2;

                        }//if

                }//for

                if(targetIndex == -1)

                        throw new VisitException("Problemas durante el spatial join, no se encontr? un vecino mas proximo");

                IFeature joinedFeature;

                        joinedFeature = createFeature(g, sourceIndex, targetIndex);

                        this.featureProcessor.processFeature(joinedFeature);

long t1 = System.currentTimeMillis();

System.out.println((t1-t0)+" en spatial join con indice espacial");

                } catch (DriverException e) {

                        throw new VisitException("Error de driver al escribir un feature resultante de un spatial join", e);

                } catch (com.hardcode.gdbms.engine.data.driver.DriverException e) {

                        throw new VisitException("Error de driver al escribir un feature resultante de un spatial join", e);

                } catch (DriverIOException e) {

                        throw new VisitException("Error accediendo a datos de la capa destino en spatial join", e);

                }

        }

}