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.xml.xml2json.handler;
029
030import org.opencms.main.CmsLog;
031import org.opencms.xml.xml2json.CmsJsonResult;
032
033import javax.servlet.http.HttpServletResponse;
034
035import org.apache.commons.logging.Log;
036
037import org.json.JSONObject;
038
039/**
040 * Wrapper around a JSON handler that catches exceptions.
041 */
042public class CmsExceptionSafeHandlerWrapper implements I_CmsJsonHandler {
043
044    /** Logger instance for this class. */
045    private static final Log LOG = CmsLog.getLog(CmsExceptionSafeHandlerWrapper.class);
046
047    /** The wrapped handler. */
048    private I_CmsJsonHandler m_handler;
049
050    /**
051     * Creates a new instance.
052     *
053     * @param handler the handler to wrap
054     */
055    public CmsExceptionSafeHandlerWrapper(I_CmsJsonHandler handler) {
056
057        m_handler = handler;
058    }
059
060    /**
061     * @see org.opencms.xml.xml2json.handler.I_CmsJsonHandler#getOrder()
062     */
063    public double getOrder() {
064
065        return m_handler.getOrder();
066    }
067
068    /**
069     * @see org.opencms.xml.xml2json.handler.I_CmsJsonHandler#matches(org.opencms.xml.xml2json.handler.CmsJsonHandlerContext)
070     */
071    public boolean matches(CmsJsonHandlerContext context) {
072
073        try {
074            return m_handler.matches(context);
075        } catch (Exception e) {
076            LOG.error(e.getLocalizedMessage(), e);
077            return false;
078        }
079    }
080
081    /**
082     * @see org.opencms.xml.xml2json.handler.I_CmsJsonHandler#renderJson(org.opencms.xml.xml2json.handler.CmsJsonHandlerContext)
083     */
084    public CmsJsonResult renderJson(CmsJsonHandlerContext context) {
085
086        try {
087            return m_handler.renderJson(context);
088        } catch (Exception e) {
089            LOG.error(e.getLocalizedMessage(), e);
090            return new CmsJsonResult(
091                JSONObject.quote(e.getLocalizedMessage()),
092                HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
093        }
094    }
095
096    /**
097     * @see java.lang.Object#toString()
098     */
099    @Override
100    public String toString() {
101
102        return m_handler.toString();
103    }
104
105}