    001    /*
    002     * Licensed to the Apache Software Foundation (ASF) under one or more
    003     * contributor license agreements.  See the NOTICE file distributed with
    004     * this work for additional information regarding copyright ownership.
    005     * The ASF licenses this file to You under the Apache License, Version 2.0
    006     * (the "License"); you may not use this file except in compliance with
    007     * the License.  You may obtain a copy of the License at
    008     *
    009     *     http://www.apache.org/licenses/LICENSE-2.0
    010     *
    011     * Unless required by applicable law or agreed to in writing, software
    012     * distributed under the License is distributed on an "AS IS" BASIS,
    013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014     * See the License for the specific language governing permissions and
    015     * limitations under the License.
    016     */
    017    package org.apache.commons.jxpath.servlet;
    018
    019    import java.util.Enumeration;
    020    import java.util.HashSet;
    021    import javax.servlet.http.HttpSession;
    022
    023    import org.apache.commons.jxpath.JXPathException;
    024
    025    /**
    026     * Implementation of the {@link org.apache.commons.jxpath.DynamicPropertyHandler}
    027     * interface that provides access to attributes of a @{link HttpSession}.
    028     *
    029     * @author Dmitri Plotnikov
    030     * @version $Revision: 652845 $ $Date: 2008-05-02 12:46:46 -0500 (Fri, 02 May 2008) $
    031     */
    032    public class HttpSessionHandler extends ServletContextHandler {
    033
    034        protected void collectPropertyNames(HashSet set, Object bean) {
    035            HttpSessionAndServletContext handle =
    036                (HttpSessionAndServletContext) bean;
    037            super.collectPropertyNames(set, handle.getServletContext());
    038            HttpSession session = handle.getSession();
    039            if (session != null) {
    040                Enumeration e = session.getAttributeNames();
    041                while (e.hasMoreElements()) {
    042                    set.add(e.nextElement());
    043                }
    044            }
    045        }
    046
    047        public Object getProperty(Object bean, String property) {
    048            HttpSessionAndServletContext handle =
    049                (HttpSessionAndServletContext) bean;
    050            HttpSession session = handle.getSession();
    051            if (session != null) {
    052                Object object = session.getAttribute(property);
    053                if (object != null) {
    054                    return object;
    055                }
    056            }
    057            return super.getProperty(handle.getServletContext(), property);
    058        }
    059
    060        public void setProperty(Object bean, String property, Object value) {
    061            HttpSessionAndServletContext handle =
    062                (HttpSessionAndServletContext) bean;
    063            HttpSession session = handle.getSession();
    064            if (session != null) {
    065                session.setAttribute(property, value);
    066            }
    067            else {
    068                throw new JXPathException("Cannot set session attribute: "
    069                        + "there is no session");
    070            }
    071        }
    072    }