/* * File : $Source: /alkacon/cvs/alkacon/com.alkacon.opencms.v8.newsletter/src/com/alkacon/opencms/v8/newsletter/CmsNewsletterDateResourceComparator.java,v $ * Date : $Date: 2010-10-14 12:44:53 $ * Version: $Revision: 1.1 $ * * This library is part of OpenCms - * the Open Source Content Management System * * Copyright (c) 2002 - 2009 Alkacon Software GmbH (http://www.alkacon.com) * * 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. * * For further information about Alkacon Software GmbH, please see the * company website: http://www.alkacon.com * * For further information about OpenCms, please see the * project website: http://www.opencms.org * * 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 */ package com.alkacon.opencms.v8.newsletter; import org.opencms.file.CmsObject; import org.opencms.file.CmsProperty; import org.opencms.file.CmsResource; import org.opencms.file.collectors.CmsDateResourceComparator; import org.opencms.main.CmsException; import org.opencms.util.CmsStringUtil; import org.opencms.util.CmsUUID; import java.util.Comparator; import java.util.HashMap; import java.util.List; import java.util.Map; /** * Comparator for sorting newsletter resource objects based on dates.<p> * * Serves as {@link java.util.Comparator} for resources and as comparator key for the resource * at the same time. Uses lazy initializing of comparator keys for a resource.<p> * * @author Andreas Zahner * * @version $Revision: 1.1 $ * * @since 7.9.2 */ public class CmsNewsletterDateResourceComparator implements Comparator<CmsResource> { /** The date sort order. */ private boolean m_asc; /** The current OpenCms user context. */ private CmsObject m_cms; /** The date of this comparator key. */ private long m_date; /** The internal map of comparator keys. */ private Map<CmsUUID, CmsNewsletterDateResourceComparator> m_keys; /** * Creates a new instance of this comparator key.<p> * * @param cms the current OpenCms user context * @param asc if true, the date sort order is ascending, otherwise descending */ public CmsNewsletterDateResourceComparator(CmsObject cms, boolean asc) { m_cms = cms; m_asc = asc; m_keys = new HashMap<CmsUUID, CmsNewsletterDateResourceComparator>(); } /** * Creates a new, empty instance of this comparator key, used for the calculated map valued.<p> */ private CmsNewsletterDateResourceComparator() { // NOOP } /** * Calculates the date to use for comparison of this resource based on the given date identifiers.<p> * * @param cms the current OpenCms user context * @param resource the resource to create the key for * @param defaultValue the default value to use in case no value can be calculated * * @return the calculated date * * @see CmsDateResourceComparator for a description about how the date identifieres are used */ public static long calculateDate(CmsObject cms, CmsResource resource, long defaultValue) { long result = 0; String propValue = ""; try { propValue = cms.readPropertyObject(resource, CmsNewsletterManager.PROPERTY_NEWSLETTER_DATA, false).getValue(); } catch (CmsException e) { // failed to read the property, ignore } if (CmsStringUtil.isNotEmptyOrWhitespaceOnly(propValue)) { // there is a value set for the property List<String> valueParts = CmsStringUtil.splitAsList(propValue, CmsProperty.VALUE_LIST_DELIMITER, true); try { result = Long.parseLong(valueParts.get(0)); resource.setDateReleased(result); } catch (NumberFormatException e) { // ignore, the default value is used } } if (result == 0) { // if nothing else was found, use default result = defaultValue; } return result; } /** * Creates a new instance of this comparator key.<p> * * @param cms the current OpenCms user context * @param resource the resource to create the key for * * @return a new instance of this comparator key */ private static CmsNewsletterDateResourceComparator create(CmsObject cms, CmsResource resource) { CmsNewsletterDateResourceComparator result = new CmsNewsletterDateResourceComparator(); result.m_date = calculateDate(cms, resource, resource.getDateLastModified()); return result; } /** * Compares {@link CmsResource} objects based on the date * found in the {@link CmsNewsletterManager#PROPERTY_NEWSLETTER_DATA} property.<p> * * @param res0 the first resource to be compared * @param res1 the second resource to be compared * * @return a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second. * * @see java.util.Comparator#compare(java.lang.Object, java.lang.Object) */ public int compare(CmsResource res0, CmsResource res1) { if (res0 == res1) { return 0; } CmsNewsletterDateResourceComparator key0 = m_keys.get(res0.getStructureId()); CmsNewsletterDateResourceComparator key1 = m_keys.get(res1.getStructureId()); if (key0 == null) { // initialize key if null key0 = CmsNewsletterDateResourceComparator.create(m_cms, res0); m_keys.put(res0.getStructureId(), key0); } if (key1 == null) { // initialize key if null key1 = CmsNewsletterDateResourceComparator.create(m_cms, res1); m_keys.put(res1.getStructureId(), key1); } if (m_asc) { // sort in ascending order if (key0.m_date > key1.m_date) { return 1; } if (key0.m_date < key1.m_date) { return -1; } } else { // sort in descending order if (key0.m_date > key1.m_date) { return -1; } if (key0.m_date < key1.m_date) { return 1; } } return 0; } /** * Returns the date of this resource comparator key.<p> * * @return the date of this resource comparator key */ public long getDate() { return m_date; } }