Metacat

/**

 *  '$RCSfile$'

 *    Purpose: A Class that implements session utility methods

 *  Copyright: 2008 Regents of the University of California and the

 *             National Center for Ecological Analysis and Synthesis

 *    Authors: Michael Daigle

 *

 *   '$Author$'

 *     '$Date$'

 * '$Revision$'

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

package edu.ucsb.nceas.metacat.service;

import java.util.Calendar;

import edu.ucsb.nceas.metacat.shared.ServiceException;

	private static SessionService sessionService = null;

	private static Logger logMetacat = Logger.getLogger(SessionService.class);

	private static Hashtable<String, SessionData> sessionHash = null;

	private static Object lockObj = new Object();

	/**

	 * private constructor since this is a singleton

	 */

		_serviceName = "SessionService";

		try {

			sessionHash = new Hashtable<String, SessionData>();

			sessionTimeoutStr = PropertyService.getProperty("session.timeoutMinutes");

			sessionTimeoutMinutes = Integer.parseInt(sessionTimeoutStr);

			logMetacat.debug("SessionService() - Registering public session id: " +

					PUBLIC_SESSION_ID);

			throw new ServiceException("SessionService() - Error getting property: " +

					pnfe.getMessage());

		} catch (NumberFormatException nfe) {

			throw new ServiceException("SessionService() - Error parsing session timeout minutes: " +

					sessionTimeoutStr);

		}

	/**

	    try

	    {

	        if (sessionService == null) {

	            sessionService = new SessionService();

	        }

	        return sessionService;

	    }

	    catch(ServiceException se)

	    {

	        logMetacat.error("SessionService.getInstance - could not get " +

	                "an instance of SessionService: " + se.getMessage());

	    }

		return null;

		return false;

	}

	}

		return;

	}

	 * Register a session in the session hash table.  This uses

	 * the parameters passed in to create a SessionData object.

	 *

	 * @param sessionId

	 *            the ID of the session to register

	 * @param userName

	 *            the user name of the session

	 * @param groupNames

	 *            the group names for the session

	 * @param password

	 *            the password for the session

	 */

			if (sessionId == null) {

				throw new ServiceException("SessionService.registerSession - " +

						"Cannot register a null session id");

			}

			logMetacat.debug("SessionService.registerSession - Registering session id: " + sessionId);

			SessionData sessionData = new SessionData(sessionId, userName, groupNames,

					password, name);

			sessionHash.put(sessionId, sessionData);

	 * Register a session in the session hash table.

	 *

	 * @param sessionData

	 *            the session data object to add to the session hash

	 */

			if (sessionData == null) {

				throw new ServiceException("SessionService.registerSession - " +

						"Cannot register null session data");

			}

			logMetacat.debug("SessionService.registerSession - Registering session " +

					"data with id: " + sessionData.getId());

			sessionHash.put(sessionData.getId(), sessionData);

	 * Unregister a session from the session hash table.

	 *

	 * @param sessionId

	 *            the id of the session to remove.

	 */

			if (sessionId == null) {

				logMetacat.error("SessionService.unRegisterSession - trying to " +

				logMetacat.error("SessionService.unRegisterSession - cannot unregister public session, " +

					"sessionId=" + sessionId);

				return;

			}

			logMetacat.info("SessionService.unRegisterSession - unRegistering session: " + sessionId);

			sessionHash.remove(sessionId);

	 *

	 * @param sessionId

	 *            the id of the session to remove.

	 */

			Enumeration<String> keyEnum = sessionHash.keys();

			while (keyEnum.hasMoreElements()) {

				String sessionId = keyEnum.nextElement();

				if (!sessionId.equals(PUBLIC_SESSION_ID)) {

					logMetacat.info("SessionService.unRegisterAllSessions - unRegistering session: " + sessionId);

					sessionHash.remove(sessionId);

				}

			}

		}

	}

	/**

	 *

	 * @param sessionId

	 *            the id of the session to look for.

	 */

					"session with null id is registered");

		}

		checkTimeout(sessionId);

	}

	 * in XML format to output.

	 *

	 * @param out

	 *            the output stream to write to.

	 * @param sessionId

	 *            the id of the session to look for.

	 */

		out.println("<?xml version=\"1.0\"?>");

		out.write("<validateSession><status>");

			out.write("invalid");

		}

		out.write("</status>");

		  SessionData sessionData = getRegisteredSession(sessionId);

	    if(sessionData != null) {

	      out.write("<userInformation>");

	      out.write("<name>");

	      out.write(sessionData.getUserName());

	      out.write("</name>");

	      appendGroupsInformation(sessionData, out);

	      out.write("</userInformation>");

	    }

		}

	}

	/**

	 * true if the session is valid and false otherwise.

	 *

	 * @param sessionId

	 *            the id of the session to look for.

	 */

			return true;

		} else {

			return false;

		}

	}

	/**

	 * TODO MCD need to time sessions out

	 *

	 * @param sessionId

	 *            the id of the session to retrieve.

	 */

		}

	}

	 * Get the public session from the session hash table.

	 */

	 * Keep a session active by updating its last accessed time.

	 *

	 * @param sessionId

	 *            the id of the session to update.

	 */

				SessionData sessionData = getRegisteredSession(sessionId);

				sessionData.setLastAccessedTime();

			}

	}

		if ((sessionData = sessionHash.get(sessionId)) != null) {

			Calendar expireTime = Calendar.getInstance();

			Calendar lastAccessedTime = sessionData.getLastAccessedTime();

			expireTime.add(Calendar.MINUTE, 0 - sessionTimeoutMinutes);

			if(lastAccessedTime.compareTo(expireTime) < 0 ) {

				unRegisterSession(sessionId);

			}

	/*

	 * Add user's groups information into the response

	 */

	private void appendGroupsInformation(SessionData sessionData, PrintWriter out ) {

	  if(sessionData != null && out != null){

	    String[] groups = sessionData.getGroupNames();

	    if(groups != null) {

	      for(String groupName : groups) {

	        out.write("<group>");

	        out.write(groupName);

	        out.write("</group>");

	      }

	    }

	  }

	}

}