001/*
002 * This library is part of OpenCms -
003 * the Open Source Content Management System
004 *
005 * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
006 *
007 * This library is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * This library is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
015 * Lesser General Public License for more details.
016 *
017 * For further information about Alkacon Software GmbH & Co. KG, please see the
018 * company website: http://www.alkacon.com
019 *
020 * For further information about OpenCms, please see the
021 * project website: http://www.opencms.org
022 *
023 * You should have received a copy of the GNU Lesser General Public
024 * License along with this library; if not, write to the Free Software
025 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
026 */
027
028package org.opencms.db.mssql;
029
030import org.opencms.db.generic.CmsSqlManager;
031import org.opencms.db.generic.CmsUserQueryBuilder;
032
033import com.google.common.base.Joiner;
034
035/**
036 * MS SQL implementation of the user driver methods.<p>
037 *
038 * @since 6.0.0
039 */
040public class CmsUserDriver extends org.opencms.db.generic.CmsUserDriver {
041
042    /** Records whether this driver class has been instantiated. */
043    private static boolean m_isInstantiated;
044
045    /**
046     * Creates a new driver instance.<p>
047     */
048    public CmsUserDriver() {
049
050        m_isInstantiated = true;
051    }
052
053    /**
054     * Returns true if the user driver has been instantiated.<p>
055     *
056     * We use this to check whether the used database is MSSQL.
057     *
058     * TODO: Make lazy user lists work with MSSQL, too.
059     *
060     * @return true if the user driver has been instantiated
061     */
062    public static boolean isInstantiated() {
063
064        return m_isInstantiated;
065    }
066
067    /**
068     * @see org.opencms.db.generic.CmsUserDriver#createUserQueryBuilder()
069     */
070    @Override
071    public CmsUserQueryBuilder createUserQueryBuilder() {
072
073        return new CmsUserQueryBuilder() {
074
075            /**
076             * @see org.opencms.db.generic.CmsUserQueryBuilder#generateConcat(java.lang.String[])
077             */
078            @Override
079            protected String generateConcat(String... expressions) {
080
081                return Joiner.on(" + ").join(expressions);
082            }
083
084            /**
085             * @see org.opencms.db.generic.CmsUserQueryBuilder#generateTrim(java.lang.String)
086             */
087            @Override
088            protected String generateTrim(String expression) {
089
090                return "LTRIM(RTRIM(" + expression + "))";
091            }
092
093            /**
094             * @see org.opencms.db.generic.CmsUserQueryBuilder#useWindowFunctionsForPaging()
095             */
096            @Override
097            protected boolean useWindowFunctionsForPaging() {
098
099                return true;
100            }
101        };
102
103    }
104
105    /**
106     * @see org.opencms.db.I_CmsUserDriver#initSqlManager(String)
107     */
108    @Override
109    public org.opencms.db.generic.CmsSqlManager initSqlManager(String classname) {
110
111        return CmsSqlManager.getInstance(classname);
112    }
113
114}