Subversion Repositories hibernate-spatial

/**
 * $Id: AbstractDBGeometryType.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;

import java.io.Serializable;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Properties;

import org.hibernate.HibernateException;
import org.hibernate.usertype.ParameterizedType;
import org.hibernate.usertype.UserType;

import com.vividsolutions.jts.geom.Geometry;

/**
 * This type is a abstract base type for implemenating database specific user
 * types for geometry types.
 * 
 * @author Karel Maesen
 */
public abstract class AbstractDBGeometryType implements UserType,
        ParameterizedType {

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#assemble(java.io.Serializable,
     *      java.lang.Object)
     */
    public Object assemble(Serializable cached, Object owner)
            throws HibernateException {
        return cached;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#deepCopy(java.lang.Object)
     */
    public Object deepCopy(Object value) throws HibernateException {
        return value;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#disassemble(java.lang.Object)
     */
    public Serializable disassemble(Object value) throws HibernateException {
        return (Serializable) value;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#equals(java.lang.Object,
     *      java.lang.Object)
     */
    public boolean equals(Object x, Object y) throws HibernateException {
        if (x == y)
            return true;
        if (x == null || y == null)
            return false;
        return ((Geometry) x).equalsExact((Geometry) y);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#hashCode(java.lang.Object)
     */
    public int hashCode(Object x) throws HibernateException {
        return x.hashCode();
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#isMutable()
     */
    public boolean isMutable() {
        return false;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#nullSafeGet(java.sql.ResultSet,
     *      java.lang.String[], java.lang.Object)
     */
    public Object nullSafeGet(ResultSet rs, String[] names, Object owner)
            throws HibernateException, SQLException {
        Object geomObj = rs.getObject(names[0]);
        return convert2JTS(geomObj);
    }

    /**
     * Converts the native database geometry object to a JTS Geometry object.
     * 
     * Concrete subclasses should override this method.
     * 
     * @param geomObj
     *            native database geometry object
     * @return JTS Geometry
     */
    public abstract Geometry convert2JTS(Object geomObj);

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#nullSafeSet(java.sql.PreparedStatement,
     *      java.lang.Object, int)
     */
    public void nullSafeSet(PreparedStatement st, Object value, int index)
            throws HibernateException, SQLException {
        if (value == null) {
            st.setNull(index, sqlTypes()[0]);
        } else {
            Geometry jtsGeom = (Geometry) value;
            Object dbGeom = conv2DBGeometry(jtsGeom, st.getConnection());
            st.setObject(index, dbGeom);
        }
    }

    /**
     * Converts a JTS geometry object to a native database geometry object.
     * 
     * Concrete subclasses should override this method.
     * 
     * @param geomObj
     *            JTS Geometry
     * @return native database geometry object
     */
    public abstract Object conv2DBGeometry(Geometry jtsGeom,
            Connection connection);

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#replace(java.lang.Object,
     *      java.lang.Object, java.lang.Object)
     */
    public Object replace(Object original, Object target, Object owner)
            throws HibernateException {
        return original;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#returnedClass()
     */
    public Class returnedClass() {
        return Geometry.class;
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.UserType#sqlTypes()
     * 
     * This should be overriden by concrete subclasses
     */
    public abstract int[] sqlTypes();

    /*
     * (non-Javadoc)
     * 
     * @see org.hibernate.usertype.ParameterizedType#setParameterValues(java.util.Properties)
     */
    public void setParameterValues(Properties parameters) {
    }

}