001    /**
002     * Copyright (c) 2000-2010 Liferay, Inc. All rights reserved.
003     *
004     * This library is free software; you can redistribute it and/or modify it under
005     * the terms of the GNU Lesser General Public License as published by the Free
006     * Software Foundation; either version 2.1 of the License, or (at your option)
007     * any later version.
008     *
009     * This library is distributed in the hope that it will be useful, but WITHOUT
010     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
011     * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
012     * details.
013     */
014    
015    package com.liferay.portlet.messageboards.util.comparator;
016    
017    import com.liferay.portal.kernel.dao.db.DB;
018    import com.liferay.portal.kernel.dao.db.DBFactoryUtil;
019    import com.liferay.portal.kernel.util.DateUtil;
020    import com.liferay.portal.kernel.util.OrderByComparator;
021    import com.liferay.portlet.messageboards.model.MBThread;
022    
023    import java.util.Date;
024    
025    /**
026     * @author Brian Wing Shun Chan
027     */
028    public class ThreadLastPostDateComparator extends OrderByComparator {
029    
030            public static String ORDER_BY_ASC = "lastPostDate ASC, threadId ASC";
031    
032            public static String ORDER_BY_DESC = "lastPostDate DESC, threadId DESC";
033    
034            public static String[] ORDER_BY_FIELDS = {"lastPostDate", "threadId"};
035    
036            public ThreadLastPostDateComparator() {
037                    this(false);
038            }
039    
040            public ThreadLastPostDateComparator(boolean ascending) {
041                    _ascending = ascending;
042            }
043    
044            public int compare(Object obj1, Object obj2) {
045                    MBThread thread1 = (MBThread)obj1;
046                    MBThread thread2 = (MBThread)obj2;
047    
048                    Date lastPostDate1 = thread1.getLastPostDate();
049                    Date lastPostDate2 = thread2.getLastPostDate();
050    
051                    boolean ignoreMilliseconds = false;
052    
053                    DB db = DBFactoryUtil.getDB();
054    
055                    if (!db.isSupportsDateMilliseconds()) {
056                            ignoreMilliseconds = true;
057                    }
058    
059                    int value = DateUtil.compareTo(
060                            lastPostDate1, lastPostDate2, ignoreMilliseconds);
061    
062                    if (value == 0) {
063                            if (thread1.getThreadId() < thread2.getThreadId()) {
064                                    value = -1;
065                            }
066                            else if (thread1.getThreadId() > thread2.getThreadId()) {
067                                    value = 1;
068                            }
069                    }
070    
071                    if (_ascending) {
072                            return value;
073                    }
074                    else {
075                            return -value;
076                    }
077            }
078    
079            public String getOrderBy() {
080                    if (_ascending) {
081                            return ORDER_BY_ASC;
082                    }
083                    else {
084                            return ORDER_BY_DESC;
085                    }
086            }
087    
088            public String[] getOrderByFields() {
089                    return ORDER_BY_FIELDS;
090            }
091    
092            public boolean isAscending() {
093                    return _ascending;
094            }
095    
096            private boolean _ascending;
097    
098    }