Subversion Repositories hibernate-spatial

/**
 * $Id: SpatialFilter.java 40 2007-09-20 15:33:24Z maesenka $
 *
 * This file is part of Spatial Hibernate, an extension to the 
 * hibernate ORM solution for geographic data. 
 *  
 * Copyright © 2007 K.U. Leuven LRD, Spatial Applications Division, Belgium
 *
 * This work was partially supported by the European Commission, 
 * under the 6th Framework Programme, contract IST-2-004688-STP.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * For more information, visit: http://www.cadrie.com/
 */

package org.hibernatespatial.criterion;

import org.hibernate.Criteria;
import org.hibernate.HibernateException;
import org.hibernate.criterion.CriteriaQuery;
import org.hibernate.criterion.Criterion;
import org.hibernate.dialect.Dialect;
import org.hibernate.engine.SessionFactoryImplementor;
import org.hibernate.engine.TypedValue;
import org.hibernatespatial.SpatialDialect;
import org.hibernatespatial.helper.EnvelopeAdapter;

import com.vividsolutions.jts.geom.Envelope;
import com.vividsolutions.jts.geom.Geometry;

/**
 * An implementation for a simple spatial filter. This <code>Criterion</code>
 * restricts the resultset to those features whose bounding box overlaps the
 * filter geometry. It is intended for quick, but inexact spatial queries.
 * 
 * @author Karel Maesen
 */
public class SpatialFilter implements Criterion {

    private static final long serialVersionUID = 1L;

    private String propertyName = null;

    private Geometry filter = null;

    public SpatialFilter(String propertyName, Geometry filter) {
        this.propertyName = propertyName;
        this.filter = filter;
    }

    public SpatialFilter(String propertyName, Envelope envelope, int SRID) {
        this.propertyName = propertyName;
        this.filter = EnvelopeAdapter.toPolygon(envelope, SRID);

    }

    public TypedValue[] getTypedValues(Criteria criteria,
            CriteriaQuery criteriaQuery) throws HibernateException {
        return new TypedValue[] { criteriaQuery.getTypedValue(criteria,
                propertyName, filter) };
    }

    public String toSqlString(Criteria criteria, CriteriaQuery criteriaQuery)
            throws HibernateException {
        SessionFactoryImplementor factory = criteriaQuery.getFactory();
        String[] columns = criteriaQuery.getColumnsUsingProjection(criteria,
                this.propertyName);
        Dialect dialect = factory.getDialect();
        if (dialect instanceof SpatialDialect) {
            SpatialDialect seDialect = (SpatialDialect) dialect;
            return seDialect.getSpatialFilterExpression(columns[0]);
        } else
            throw new IllegalStateException(
                    "Dialect must be spatially enabled dialect");

    }

}