org.objectstyle.cayenne.dba.derby.DerbyPkGenerator Maven / Gradle / Ivy

Show more of this group Show more artifacts with this name
Show all versions of cayenne
Cayenne Object Persistence Framework including all dependencies.
The newest version!
/* ====================================================================
 * 
 * The ObjectStyle Group Software License, version 1.1
 * ObjectStyle Group - http://objectstyle.org/
 * 
 * Copyright (c) 2002-2005, Andrei (Andrus) Adamchik and individual authors
 * of the software. All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 
 * 3. The end-user documentation included with the redistribution, if any,
 *    must include the following acknowlegement:
 *    "This product includes software developed by independent contributors
 *    and hosted on ObjectStyle Group web site (http://objectstyle.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 * 
 * 4. The names "ObjectStyle Group" and "Cayenne" must not be used to endorse
 *    or promote products derived from this software without prior written
 *    permission. For written permission, email
 *    "andrus at objectstyle dot org".
 * 
 * 5. Products derived from this software may not be called "ObjectStyle"
 *    or "Cayenne", nor may "ObjectStyle" or "Cayenne" appear in their
 *    names without prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE OBJECTSTYLE GROUP OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 * 
 * This software consists of voluntary contributions made by many
 * individuals and hosted on ObjectStyle Group web site.  For more
 * information on the ObjectStyle Group, please see
 * .
 */
package org.objectstyle.cayenne.dba.derby;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.Collections;

import org.objectstyle.cayenne.CayenneException;
import org.objectstyle.cayenne.access.DataNode;
import org.objectstyle.cayenne.access.QueryLogger;
import org.objectstyle.cayenne.dba.JdbcPkGenerator;
import org.objectstyle.cayenne.map.DbEntity;

/**
 * Default PK generator for Derby that uses updateable ResultSet to get the next id from
 * the lookup table.
 * 
 * @since 1.2
 * @author Andrus Adamchik
 */
public class DerbyPkGenerator extends JdbcPkGenerator {

    static final String SELECT_QUERY = "SELECT NEXT_ID FROM AUTO_PK_SUPPORT"
            + " WHERE TABLE_NAME = ? FOR UPDATE";

    protected int pkFromDatabase(DataNode node, DbEntity entity) throws Exception {

        if (QueryLogger.isLoggable()) {
            QueryLogger.logQuery(SELECT_QUERY, Collections
                    .singletonList(entity.getName()));
        }

        Connection c = node.getDataSource().getConnection();

        try {
            PreparedStatement select = c.prepareStatement(
                    SELECT_QUERY,
                    ResultSet.TYPE_FORWARD_ONLY,
                    ResultSet.CONCUR_UPDATABLE);

            select.setString(1, entity.getName());
            ResultSet rs = select.executeQuery();

            if (!rs.next()) {
                throw new CayenneException("PK lookup failed for table: "
                        + entity.getName());
            }

            int nextId = rs.getInt(1);

            rs.updateInt(1, nextId + pkCacheSize);
            rs.updateRow();

            if (rs.next()) {
                throw new CayenneException("More than one PK record for table: "
                        + entity.getName());
            }
            
            rs.close();

            select.close();
            c.commit();

            return nextId;
        }
        finally {
            c.close();
        }
    }
}