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, 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.ade.upload;
029
030import org.opencms.main.CmsLog;
031
032import java.io.Serializable;
033import java.util.Date;
034
035import org.apache.commons.logging.Log;
036
037/**
038 * A class which is executed in a new thread, so its able to detect
039 * when an upload process is frozen and sets an exception in order to
040 * be canceled. This doesn't work in Google application engine.<p>
041 */
042public class CmsUploadTimeoutWatcher extends Thread implements Serializable {
043
044    /** The log object for this class. */
045    private static final Log LOG = CmsLog.getLog(CmsUploadTimeoutWatcher.class);
046
047    /** The serial version UID. */
048    private static final long serialVersionUID = -649803529271569237L;
049
050    /** The watchers interval. */
051    private static final int WATCHER_INTERVAL = 5000;
052
053    /** Last bytes read. */
054    private long m_lastBytesRead;
055
056    /** Timestamp for the last received data. */
057    private long m_lastData = (new Date()).getTime();
058
059    /** The listener to watch. */
060    private CmsUploadListener m_listener;
061
062    /**
063     * A public constructor.<p>
064     *
065     * @param listener the listener to watch
066     */
067    public CmsUploadTimeoutWatcher(CmsUploadListener listener) {
068
069        m_listener = listener;
070    }
071
072    /**
073     * Cancels the watch process.<p>
074     */
075    public void cancel() {
076
077        m_listener = null;
078    }
079
080    /**
081     * The watching process.<p>
082     *
083     * @see java.lang.Thread#run()
084     */
085    @Override
086    public void run() {
087
088        try {
089            Thread.sleep(WATCHER_INTERVAL);
090        } catch (InterruptedException e) {
091            LOG.error(Messages.get().container(Messages.ERR_UPLOAD_INTERRUPT_WATCH_DOG_1, m_listener.toString()), e);
092        }
093        if (m_listener != null) {
094            if (((m_listener.getBytesRead() > 0) && (m_listener.getPercent() >= 100)) || m_listener.isCanceled()) {
095                LOG.debug(Messages.get().container(Messages.LOG_UPLOAD_FINISHED_WATCHER_1, m_listener.toString()));
096                m_listener = null;
097            } else {
098                if (isFrozen()) {
099                    m_listener.cancelUpload(new CmsUploadException(
100                        Messages.get().getBundle().key(
101                            Messages.ERR_UPLOAD_FROZEN_1,
102                            Integer.valueOf(CmsUploadBean.DEFAULT_UPLOAD_TIMEOUT / 1000))));
103                } else {
104                    run();
105                }
106            }
107        }
108    }
109
110    /**
111     * Returns <code>true</code> if the upload process is frozen.<p>
112     *
113     * @return <code>true</code> if the upload process is frozen
114     */
115    private boolean isFrozen() {
116
117        long now = (new Date()).getTime();
118
119        if (m_listener.getBytesRead() > m_lastBytesRead) {
120            m_lastData = now;
121            m_lastBytesRead = m_listener.getBytesRead();
122        } else if ((now - m_lastData) > CmsUploadBean.DEFAULT_UPLOAD_TIMEOUT) {
123            return true;
124        }
125        return false;
126    }
127}