001/*
002 * Copyright 2023 Web-Legacy
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.apache.tiles.request.jakarta.servlet.extractor;
017
018import java.util.Collections;
019import java.util.Enumeration;
020
021import org.apache.tiles.request.attribute.AttributeExtractor;
022
023import jakarta.servlet.http.HttpServletRequest;
024import jakarta.servlet.http.HttpSession;
025
026/**
027 * Extract attributes from session scope.
028 *
029 * <p>Copied from Apache tiles-request-servlet 1.0.7 and adapted for
030 * Jakarta EE 9.</p>
031 */
032public class SessionScopeExtractor implements AttributeExtractor {
033
034    /**
035     * The servlet request.
036     */
037    private HttpServletRequest request;
038
039    /**
040     * Constructor.
041     *
042     * @param request The servlet request.
043     */
044    public SessionScopeExtractor(HttpServletRequest request) {
045        this.request = request;
046    }
047
048    /**
049     * Sets a value for the given key.
050     *
051     * @param name  The key of the attribute.
052     * @param value The value of the attribute.
053     */
054    @Override
055    public void setValue(String name, Object value) {
056        request.getSession().setAttribute(name, value);
057    }
058
059    /**
060     * Removes an attribute.
061     *
062     * @param name The key of the attribute to remove.
063     */
064    @Override
065    public void removeValue(String name) {
066        HttpSession session = request.getSession(false);
067        if (session != null) {
068            session.removeAttribute(name);
069        }
070    }
071
072    /**
073     * The enumeration of the keys in the stored attributes.
074     *
075     * @return The keys.
076     */
077    @Override
078    public Enumeration<String> getKeys() {
079        HttpSession session = request.getSession(false);
080        if (session != null) {
081            return session.getAttributeNames();
082        }
083
084        return Collections.enumeration(Collections.<String>emptySet());
085    }
086
087    /**
088     * Returns the value of the attribute with the given key.
089     *
090     * @param key The key of the attribute.
091     *
092     * @return The value.
093     */
094    @Override
095    public Object getValue(String key) {
096        HttpSession session = request.getSession(false);
097        if (session != null) {
098            return session.getAttribute(key);
099        }
100
101        return null;
102    }
103}