/*

  * $Id: SessionScopeExtractor.java 1199216 2011-11-08 12:25:24Z mck $

  *

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you under the Apache License, Version 2.0 (the

  * "License"); you may not use this file except in compliance

  * with the License.  You may obtain a copy of the License at

  *

  * http://www.apache.org/licenses/LICENSE-2.0

  *

  * Unless required by applicable law or agreed to in writing,

  * software distributed under the License is distributed on an

  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

  * KIND, either express or implied.  See the License for the

  * specific language governing permissions and limitations

  * under the License.

  */

 package org.apache.tiles.request.servlet.extractor;

 import java.util.Enumeration;

 import java.util.Collections;

 import javax.servlet.http.HttpServletRequest;

 import javax.servlet.http.HttpSession;

 import org.apache.tiles.request.attribute.AttributeExtractor;

 /**

  * Extract attributes from session scope.

  *

  * @version $Rev: 1199216 $ $Date: 2011-11-08 23:25:24 +1100 (Tue, 08 Nov 2011) $

  */

 public class SessionScopeExtractor implements AttributeExtractor {

     /**

      * The servlet request.

      */

     private HttpServletRequest request;

     /**

      * Constructor.

      *

      * @param request The servlet request.

      */

     public SessionScopeExtractor(HttpServletRequest request) {

         this.request = request;

     }

     @Override

     public void setValue(String name, Object value) {

         request.getSession().setAttribute(name, value);

     }

     @Override

     public void removeValue(String name) {

         HttpSession session = request.getSession(false);

         if (session != null) {

             session.removeAttribute(name);

         }

     }

     @SuppressWarnings("unchecked")

     @Override

     public Enumeration<String> getKeys() {

         HttpSession session = request.getSession(false);

         if (session != null) {

             return session.getAttributeNames();

         }

         return Collections.enumeration(Collections.<String>emptySet());

     }

     @Override

     public Object getValue(String key) {

         HttpSession session = request.getSession(false);

         if (session != null) {

             return session.getAttribute(key);

         }

         return null;

     }

 }