String sessionid = null;
	    Cookie[] cookies = request.getCookies();



	    // Check to see if you need to clear session data
	    if (request.getParameter("clear") != null){
	    	Cookie cookie = new Cookie("sessionid", "");
	        cookie.setMaxAge(0);
	        response.addCookie(cookie);
	        response.sendRedirect("");
	    }

	    if (cookies != null) {
	      for (int i = 0; i < cookies.length; i++) {
	        if (cookies[i].getName().equals("sessionid")) {
	          sessionid = cookies[i].getValue();
	          break;
	        }
	      }
	    }

private static String generateSessionId() throws UnsupportedEncodingException {
	    String uid = new java.rmi.server.UID().toString(); // guaranteed unique
	    return URLEncoder.encode(uid,"UTF-8"); // encode any special chars
	}
	    // If the session ID wasn't sent, generate one.
	    // Then be sure to send it to the client with the response.
	    if (sessionid == null) {
	      sessionid = generateSessionId();
	      Cookie c = new Cookie("sessionid", sessionid);
	      response.addCookie(c);
	      out.println("hello new person");
	    } else {
	    	out.println("welcome back" + sessionid);
	    }