Metacat

import java.util.Enumeration;

import java.util.Hashtable;

import javax.servlet.http.Cookie;

import javax.servlet.http.HttpSession;

import edu.ucsb.nceas.metacat.service.SessionService;

	/**

	 * Get a cookie from a request by the cookie name

	 * 

	 * @param request

	 *            the request from which to get the cookie

	 * @param cookieName

	 *            the name of the cookie to look for

	 */

	public static Cookie getCookie(HttpServletRequest request, String cookieName)  {

		Cookie sessionCookies[] = request.getCookies();

		if (sessionCookies == null) {

			return null;

		}

		for (int i = 0; i < sessionCookies.length; i++) {

			if(sessionCookies[i].getName().equals(cookieName)) {

				return sessionCookies[i];

			}

		}	

		return null;

	}

	 * Get the session data from a request. The Scenarios we can run across

	 * here: 

	 * -- the session id parameter was set in the request parameters 

	 * -- request.getSession returns a new session. There is a chance that the

	 *    session id was set in a cookie. Check for a JSESSIONID cookie and use

	 *    that id if provided. 

	 * -- request.getSession returns a session that is a)

	 *    preexisting or b) new but without a JSESSIONID cookie. Use the session id

	 *    from this session

	 * 

	 * @param request

	 *            the request from which to get the session data

	 * @return the session data object representing the active session for this

	 *         request. If there is no active session, the public session data

	 *         is returned

	 */

	public static SessionData getSessionData(HttpServletRequest request) {

		SessionData sessionData = null;

		String sessionId = null;

		Hashtable<String, String[]> params = getParameters(request);

		if (params.containsKey("sessionid")) {

			// the session id is specified in the request parameters

			sessionId = ((String[]) params.get("sessionid"))[0];

			logMetacat.debug("session ID provided in request properties: " + sessionId);

		} else {

			HttpSession session = request.getSession(true);

			if (session.isNew()) {

				// this is a new session

				Cookie sessionCookie = RequestUtil.getCookie(request, "JSESSIONID");

				if (sessionCookie != null) {

					// and there is a JSESSIONID cookie

					sessionId = sessionCookie.getValue();

					logMetacat.debug("session ID provided in request cookie: "

							+ sessionId);

				}

			}

			if (sessionId == null) {

				// there is an existing session (session is old)

				sessionId = session.getId();

				logMetacat.debug("session ID retrieved from request: " + sessionId);

			}

		}

		// if the session id is registered in SessionService, get the

		// SessionData for it. Otherwise, use the public session.

		if (SessionService.isSessionRegistered(sessionId)) {

			logMetacat.debug("retrieving session data from session service "

					+ "for session id " + sessionId);

			sessionData = SessionService.getRegisteredSession(sessionId);

		} else {

			logMetacat.debug("using public session.  Given session id is "

					+ "registered: " + sessionId);

			sessionData = SessionService.getPublicSession();

		}

		return sessionData;

	}

	/**

	 * Get a cookie from a request by the cookie name

	 * 

	 * @param request

	 *            the request from which to get the cookie

	 * @param cookieName

	 *            the name of the cookie to look for

	 */

	public static Hashtable<String, String[]> getParameters(HttpServletRequest request)  {

		Hashtable<String, String[]> params = new Hashtable<String, String[]>();

		Enumeration<String> paramlist = (Enumeration<String>)request.getParameterNames();

		while (paramlist.hasMoreElements()) {

			String name = (String) paramlist.nextElement();

			String[] value = request.getParameterValues(name);

			params.put(name, value);

		}

		return params;

	}

	/**