Java tutorial
/* * This library is part of OpenCms - * the Open Source Content Management System * * Copyright (c) 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 org.opencms.main; import javax.servlet.ServletContextEvent; import javax.servlet.ServletContextListener; import javax.servlet.http.HttpSessionEvent; import javax.servlet.http.HttpSessionListener; import org.apache.commons.logging.Log; /** * Provides the OpenCms system with information from the servlet context.<p> * * Used for the following purposes:<ul> * <li>Starting up OpenCms when the servlet container is started.</li> * <li>Shutting down OpenCms when the servlet container is shut down.</li> * <li>Informing the <code>{@link org.opencms.main.CmsSessionManager}</code> if a new session is created.</li> * <li>Informing the <code>{@link org.opencms.main.CmsSessionManager}</code> session is destroyed or invalidated.</li> * </ul> * * @since 6.0.0 */ public class OpenCmsListener implements ServletContextListener, HttpSessionListener { /** The log object for this class. */ private static final Log LOG = CmsLog.getLog(OpenCmsListener.class); /** * @see javax.servlet.ServletContextListener#contextDestroyed(javax.servlet.ServletContextEvent) */ public void contextDestroyed(ServletContextEvent event) { try { // destroy the OpenCms instance OpenCmsCore.getInstance().shutDown(); } catch (CmsInitException e) { if (e.isNewError()) { LOG.error(e.getLocalizedMessage(), e); } } catch (Throwable t) { // make sure all other errors are displayed in the OpenCms log LOG.error(Messages.get().getBundle().key(Messages.LOG_ERROR_GENERIC_0), t); } } /** * @see javax.servlet.ServletContextListener#contextInitialized(javax.servlet.ServletContextEvent) */ public void contextInitialized(ServletContextEvent event) { try { // upgrade the OpenCms runlevel OpenCmsCore.getInstance().upgradeRunlevel(event.getServletContext()); } catch (CmsInitException e) { if (e.isNewError()) { // only log new init errors LOG.error(e.getLocalizedMessage(), e); } } catch (Throwable t) { // make sure all other errors are displayed in the OpenCms log LOG.error(Messages.get().getBundle().key(Messages.LOG_ERROR_GENERIC_0), t); // throw a new init Exception to make sure a "context destroyed" event is triggered throw new CmsInitException( Messages.get().container(Messages.ERR_CRITICAL_INIT_GENERIC_1, t.getMessage())); } } /** * @see javax.servlet.http.HttpSessionListener#sessionCreated(javax.servlet.http.HttpSessionEvent) */ public void sessionCreated(HttpSessionEvent event) { try { // inform the OpenCms session manager OpenCmsCore.getInstance().getSessionManager().sessionCreated(event); } catch (CmsInitException e) { if (e.isNewError()) { LOG.error(e.getLocalizedMessage(), e); } } catch (Throwable t) { // make sure all other errors are displayed in the OpenCms log LOG.error(Messages.get().getBundle().key(Messages.LOG_ERROR_GENERIC_0), t); } } /** * @see javax.servlet.http.HttpSessionListener#sessionDestroyed(javax.servlet.http.HttpSessionEvent) */ public void sessionDestroyed(HttpSessionEvent event) { try { // inform the OpenCms session manager OpenCmsCore.getInstance().getSessionManager().sessionDestroyed(event); } catch (CmsInitException e) { if (e.isNewError()) { LOG.error(e.getLocalizedMessage(), e); } } catch (Throwable t) { // make sure all other errors are displayed in the OpenCms log LOG.error(Messages.get().getBundle().key(Messages.LOG_ERROR_GENERIC_0), t); } } }