/**
 * <copyright> Copyright 2006 by Know-Center, Graz, Austria </copyright>
 * PDF-AS has been contracted by the E-Government Innovation Center EGIZ, a
 * joint initiative of the Federal Chancellery Austria and Graz University of
 * Technology.
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * http://www.osor.eu/eupl/
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 */
package at.gv.egiz.pdfas.web.helper;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import at.gv.egiz.pdfas.exceptions.web.SessionExpiredException;
import at.gv.egiz.pdfas.web.session.SessionAttributes;

/**
 * @author wprinz
 * 
 */
public class SessionHelper
{
  /**
   * The log.
   */
  private static Log log = LogFactory.getLog(SessionHelper.class);

  public static Object getSession(HttpServletRequest request) throws SessionExpiredException
  {

    HttpSession session = request.getSession(false);
    if (session == null)
    {
      String msg = "There is no session associated with this request."; //$NON-NLS-1$
      log.error(msg);
      throw new SessionExpiredException(msg);
    }

    Object sessionObject = session.getAttribute(SessionAttributes.ATTRIBUTE_SESSION_INFORMATION);
    if (sessionObject == null)
    {
      String msg = "Unable to find session data in session " + session.getId();
      log.error(msg);
      throw new SessionExpiredException(msg);
    }

    return sessionObject;
  }
}