Application: gvSIG desktop

/* gvSIG. Geographic Information System of the Valencian Government

*

* Copyright (C) 2007-2008 Infrastructures and Transports Department

* of the Valencian Government (CIT)

* 

* 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., 51 Franklin Street, Fifth Floor, Boston, 

* MA  02110-1301, USA.

* 

*/

/*

* AUTHORS (In addition to CIT):

* 2008 {{Company}}   {{Task}}

*/

package org.gvsig.fmap.data.index.spatial;

import java.util.ArrayList;

import java.util.List;

import org.apache.log4j.Logger;

import org.gvsig.fmap.data.feature.Feature;

import org.gvsig.fmap.data.feature.FeatureID;

import org.gvsig.fmap.data.index.AbstractIndex;

import org.gvsig.fmap.data.index.IndexException;

import org.gvsig.fmap.data.index.IndexParameters;

import org.gvsig.fmap.data.index.QueryParameters;

import org.gvsig.fmap.geom.Geometry;

import org.gvsig.fmap.geom.primitive.Envelope;

/**

 * This class is a wrapper for spatial indexes based on int values so that they can use 

 * FeatureID instead.

 *

 * @author jyarza

 *

 */

public abstract class AbstractIntBasedSpatialIndex extends AbstractIndex implements SpatialIndex {

        private static Logger logger = Logger.getLogger(AbstractIntBasedSpatialIndex.class);

        /** Keeps the correspondence between the int value used internally and FeatureID */        

        private List ids = new ArrayList();

        public AbstractIntBasedSpatialIndex(IndexParameters params) throws IndexException {

                super(params);

        }

        public final void delete(Envelope env, FeatureID fid) {                

                int idx = ids.indexOf(fid);

                if (idx >= 0) {

                        this.delete(env, idx);

                }

        }

        public final void insert(Envelope env, FeatureID fid) {

                ids.add(fid);

                this.insert(env, ids.size()-1);

        }

        public final List query(QueryParameters params) throws IndexException {

                long start = System.currentTimeMillis();

                try {

                        SpatialQueryParameters sqp = (SpatialQueryParameters) params;

                        List result = query(sqp.getEnvelope());

                        // replace integers by corresponding FeatureIDs in the list

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

                                int value = ((Integer) result.get(i)).intValue();

                                result.set(i, ids.get(value));

                        }

                        long end = System.currentTimeMillis();

                        logger.debug("total index query time = " + (end-start) + " millis.");

                        return result;

                } catch (ClassCastException e) {

                        throw new IndexException(e);

                }

        }

        public final void delete(Object o, FeatureID fid) {

                delete((Envelope) o, fid);

        }

        public final void insert(Object o, FeatureID fid) {

                insert((Envelope) o, fid);                

        }

        /* 

         * overrides org.gvsig.fmap.data.index.AbstractIndex.insert because these spatial indexes 

         * use the geometry envelope instead of the geometry itself.

         */

        public final void insert(Feature feat) {

                Geometry geom = (Geometry) feat.get(getFeatureAttributeDescriptor().getName());

                insert(geom.getEnvelope(), feat.getID());                

        }

        /** Spatial indexes based on int values will implement this method for insertion */

        protected abstract void insert(Envelope env, int index);

        /** Spatial indexes based on int values will implement this method for deletion */

        protected abstract void delete(Envelope env, int index);

        /** Spatial indexes based on int values will implement this method for querying */

        protected abstract List query(Envelope env) throws IndexException;

}