/*
    * $Id: SessionScopeExtractor.java 1066849 2011-02-03 16:12:39Z apetrelli $
    *
    * 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.portlet.extractor;
  
  import java.util.Enumeration;
  
  import javax.portlet.PortletRequest;
  import javax.portlet.PortletSession;
  
  import org.apache.tiles.request.attribute.AttributeExtractor;
  
  /**
   * Extracts attributes from the session scope of a portlet request.
   *
   * @version $Rev: 1066849 $ $Date: 2011-02-04 03:12:39 +1100 (Fri, 04 Feb 2011) $
   */
  public class SessionScopeExtractor implements AttributeExtractor {
  
      /**
       * The portlet request.
       */
      private PortletRequest request;
  
      /**
       * The subscope (application or portlet).
       */
      private int scope;
  
      /**
       * Constructor.
       *
       * @param request The request.
       * @param scope The subscope (application or portlet).
       */
      public SessionScopeExtractor(PortletRequest request, int scope) {
          this.request = request;
          if (scope != PortletSession.APPLICATION_SCOPE
                  && scope != PortletSession.PORTLET_SCOPE) {
              throw new IllegalArgumentException(
                      "The scope must be either APPLICATION_SCOPE or PORTLET_SCOPE");
          }
          this.scope = scope;
      }
  
      @Override
      public void setValue(String name, Object value) {
          request.getPortletSession().setAttribute(name, value, scope);
      }
  
      @Override
      public void removeValue(String name) {
          PortletSession session = request.getPortletSession(false);
          if (session != null) {
              session.removeAttribute(name, scope);
          }
      }
  
      @Override
      public Enumeration<String> getKeys() {
          PortletSession session = request.getPortletSession(false);
          if (session != null) {
              return session.getAttributeNames(scope);
          }
          return null;
      }
  
      @Override
      public Object getValue(String key) {
          PortletSession session = request.getPortletSession(false);
          if (session != null) {
              return session.getAttribute(key, scope);
          }
          return null;
      }
  }