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
018package org.apache.commons.jxpath.servlet;
019
020import java.util.Enumeration;
021import java.util.HashSet;
022
023import javax.servlet.http.HttpSession;
024
025import org.apache.commons.jxpath.JXPathException;
026
027/**
028 * Implementation of the {@link org.apache.commons.jxpath.DynamicPropertyHandler} interface that provides access to attributes of a @{link HttpSession}.
029 */
030public class HttpSessionHandler extends ServletContextHandler {
031
032    /**
033     * Constructs a new instance.
034     */
035    public HttpSessionHandler() {
036        // empty
037    }
038
039    @Override
040    protected void collectPropertyNames(final HashSet<String> set, final Object bean) {
041        final HttpSessionAndServletContext handle = (HttpSessionAndServletContext) bean;
042        super.collectPropertyNames(set, handle.getServletContext());
043        final HttpSession session = handle.getSession();
044        if (session != null) {
045            final Enumeration<String> e = session.getAttributeNames();
046            while (e.hasMoreElements()) {
047                set.add(e.nextElement());
048            }
049        }
050    }
051
052    @Override
053    public Object getProperty(final Object bean, final String property) {
054        final HttpSessionAndServletContext handle = (HttpSessionAndServletContext) bean;
055        final HttpSession session = handle.getSession();
056        if (session != null) {
057            final Object object = session.getAttribute(property);
058            if (object != null) {
059                return object;
060            }
061        }
062        return super.getProperty(handle.getServletContext(), property);
063    }
064
065    @Override
066    public void setProperty(final Object bean, final String property, final Object value) {
067        final HttpSessionAndServletContext handle = (HttpSessionAndServletContext) bean;
068        final HttpSession session = handle.getSession();
069        if (session == null) {
070            throw new JXPathException("Cannot set session attribute: " + "there is no session");
071        }
072        session.setAttribute(property, value);
073    }
074}