Metacat

/**

 *  '$RCSfile$'

 *  Copyright: 2003 Regents of the University of California.

 *

 * Author: Matthew Perry 

 * '$Date: 2006-09-11 14:22:51 -0700 (Mon, 11 Sep 2006) $'

 * '$Revision: 3040 $'

 *

 * 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

 */

package edu.ucsb.nceas.metacat.spatial;

import org.geotools.feature.FeatureType;

import org.geotools.data.shapefile.ShapefileDataStore;

import org.geotools.data.FeatureStore;

import org.geotools.data.DefaultTransaction;

import org.geotools.data.Transaction;

import org.geotools.feature.Feature;

import org.geotools.filter.Filter;

import org.geotools.filter.CompareFilter;

import org.geotools.filter.FilterFactory;

import org.geotools.filter.FilterFactoryFinder;

import org.geotools.filter.IllegalFilterException;

import org.geotools.feature.FeatureCollection;

import org.geotools.feature.FeatureCollections;

import org.apache.log4j.Logger;

import java.io.File;

import java.io.IOException;

import java.net.URI;

import java.net.URL;

import java.net.MalformedURLException;

import edu.ucsb.nceas.metacat.MetaCatUtil;

/**

 * Class providing direct read/write access to the

 * persistent spatial cache.

 */

public class SpatialDataset {

  SpatialFeatureSchema featureSchema = new SpatialFeatureSchema();

  //public String polygonShpUri = MetaCatUtil.getOption("certPath") + "data/metacat_shps/data_bounds.shp";

  //public String pointShpUri = MetaCatUtil.getOption("certPath")+ "data/metacat_shps/data_points.shp";

  FeatureCollection polygonCollection = FeatureCollections.newCollection();

  FeatureCollection pointCollection = FeatureCollections.newCollection();

  private static Logger log =

      Logger.getLogger(SpatialDataset.class.getName());

  /**

   *  empty constructor for SpatialDataset

   */

  public SpatialDataset() {

  }

  /**

   * Adds a new feature (from a SpatialDocument)

   * This is faster than insertOrUpdate but 

   * relying on this method might cause duplication

   * of docids in the spatial cache. Therefore, its really only useful when 

   * regenerating the entire cache.

   *

   * @param geomType The kind of feature to be added. Currently "polygon" and "point" supported.

   * @param feature The geotools feature to be added to the spatial cache.

   */ 

  public void add( String geomType, Feature feature ) {

     if( geomType.equals("polygon") ) {

         // Check if feature actually is a multipolygon

         if( feature != null) 

             polygonCollection.add( feature );

     } else if( geomType.equals("point") ) {

         // Check if feature actually is a multipoint

         if( feature != null) 

             pointCollection.add( feature );

     }

  }

  /**

   * Deletes given docid from the spatial cache.

   *

   * @param geomType The kind of feature to be added. Currently "polygon" and "point" supported.

   * @param docid The document to be deleted from the spatial cache.

   */

  public void delete( String geomType, String docid ) throws IOException {

    FilterFactory filterFactory = FilterFactoryFinder.createFilterFactory();

    CompareFilter filter = null;

    FeatureStore fStore = null;

    ShapefileDataStore dStore = null;

    try {

        // Create the filter

        filter = filterFactory.createCompareFilter(CompareFilter.COMPARE_EQUALS);

        filter.addLeftValue(filterFactory.createAttributeExpression("docid"));

        filter.addRightValue(filterFactory.createLiteralExpression(docid));

    } catch (IllegalFilterException e) {

        e.printStackTrace();

    }

    // Begin new transaction

    Transaction t = new DefaultTransaction("handle");

    t.putProperty( "updating spatial cache", new Integer(7) );

    String lockId = "SpatialDataset.delete";

    try {

        boolean validGeomType = false;

        if( geomType.equals("polygon") ) {

            dStore = new ShapefileDataStore( (new File( featureSchema.polygonShpUri )).toURL() );

            fStore = (FeatureStore) dStore.getFeatureSource(dStore.getTypeNames()[0]);

            validGeomType = true;

        } else if( geomType.equals("point") ) {

            dStore = new ShapefileDataStore( (new File( featureSchema.pointShpUri )).toURL() );

            fStore = (FeatureStore) dStore.getFeatureSource(dStore.getTypeNames()[0]);

            validGeomType = true;

        }

        // Initiate the transaction

        fStore.setTransaction( t );

        t.addAuthorization( lockId );

        if( validGeomType == true) {

            // Remove old feature

            fStore.removeFeatures( filter );

            // Commit changes to shapefile

            t.commit();

            log.info(" Delete docid " + docid + " from spatial cache");

        }

    } catch (MalformedURLException e) {

        e.printStackTrace();

        t.rollback(); // cancel opperations

    } catch (IOException e) {

        e.printStackTrace();

        t.rollback(); // cancel opperations

    } finally {

        // Close out the transaction

        t.close();

    }

  }

  /**

   * Either inserts or updates the spatial cache with the new

   * spatial document depending on if it currently exists.

   * Docid is also passed in for quicker searching.

   *

   * @param geomType The kind of feature to be added. Currently "polygon" and "point" supported.

   * @param feature The geotools feature to be added to the spatial cache.

   * @param docid The document id to be inserted or updated. Used to filter for existing features.

   */

  public void insertOrUpdate( String geomType, Feature feature, String docid ) throws IOException {

    FeatureCollection fColl = FeatureCollections.newCollection();

    FilterFactory filterFactory = FilterFactoryFinder.createFilterFactory();

    CompareFilter filter = null;

    FeatureStore fStore = null;

    ShapefileDataStore dStore = null;

    // Explain why geotools fails to create the projection info from the shapefile

    //log.info( " The '.prj' errors below are related to a geotools bug " +

    //          " (http://jira.codehaus.org/browse/GEOT-604) and can be ignored");

    try {

        // Create the filter

        filter = filterFactory.createCompareFilter(CompareFilter.COMPARE_EQUALS);

        filter.addLeftValue(filterFactory.createAttributeExpression("docid"));

        filter.addRightValue(filterFactory.createLiteralExpression(docid));

    } catch (IllegalFilterException e) {

        e.printStackTrace();

    }

    // Begin new transaction

    Transaction t = new DefaultTransaction("handle");

    t.putProperty( "updating spatial cache", new Integer(7) );

    String lockId = "SpatialDataset.insertOrUpdate";

    try {

        boolean validGeomType = false;

        if( geomType.equals("polygon") ) {

            dStore = new ShapefileDataStore( (new File( featureSchema.polygonShpUri )).toURL() );

            fStore = (FeatureStore) dStore.getFeatureSource(dStore.getTypeNames()[0]);

            validGeomType = true;

        } else if( geomType.equals("point") ) {

            dStore = new ShapefileDataStore( (new File( featureSchema.pointShpUri )).toURL() );

            fStore = (FeatureStore) dStore.getFeatureSource(dStore.getTypeNames()[0]);

            validGeomType = true;

        }

        // Initiate the transaction

        fStore.setTransaction( t );

        t.addAuthorization( lockId );

        if( feature != null && validGeomType == true) {

            // Remove old feature

            fStore.removeFeatures( filter );

            // Create new feature collection then add it to feature Store

            fColl.add( feature );

            fStore.addFeatures(fColl);

            // Commit changes to shapefile

            t.commit();

            log.info(" Insert or Update docid " + docid + " from spatial cache");

        }

    } catch (MalformedURLException e) {

        e.printStackTrace();

        t.rollback(); // cancel opperations

    } catch (IOException e) {

        e.printStackTrace();

        t.rollback(); // cancel opperations

    } finally {

        // Close out the transaction

        t.close();

    }

  }

  /**

   * Saves the SpatialDataset object to the spatial cache.

   */

  public void save() {

         // Save Polygons 

         try {

             URL anURL = (new File( featureSchema.polygonShpUri )).toURL();

             ShapefileDataStore polygonDatastore = new ShapefileDataStore(anURL);

             FeatureType polygonType = featureSchema.getPolygonFeatureType();

             polygonDatastore.createSchema( polygonType );

             FeatureStore polygonFeatureStore = (FeatureStore) polygonDatastore.getFeatureSource( polygonType.getTypeName() );

             polygonFeatureStore.addFeatures( polygonCollection );

             log.info(" ---- Polygons saved to " + featureSchema.polygonShpUri );

         } catch(java.net.MalformedURLException e) {

             log.error("Malformed URL Exception : "+e);

         } catch(java.io.IOException e) {

             log.error("IO Exception : "+e);

         }

         // Save Points

         try {

             URL anURL = (new File( featureSchema.pointShpUri )).toURL();

             ShapefileDataStore pointDatastore = new ShapefileDataStore(anURL);

             FeatureType pointsType = featureSchema.getPointFeatureType();

             pointDatastore.createSchema( pointsType );

             FeatureStore pointFeatureStore = (FeatureStore) pointDatastore.getFeatureSource( pointsType.getTypeName() );

             pointFeatureStore.addFeatures( pointCollection );

             log.info(" ---- Polygons saved to " + featureSchema.pointShpUri );

         } catch(java.net.MalformedURLException e) {

             log.error("Malformed URL Exception : "+e);

         } catch(java.io.IOException e) {

             log.error("IO Exception : "+e);

         }

  }

}