Problem with storing a value into session object

[thoste]

When I call a JavaServerPage with the following simple code I got a NullPointerException.
I just want to store the current date into a variable inside the session object.

...
<%@ page import="java.util.*" %>
....
<% session = request.getSession(true);

String firstVisit = (String) session.getAttribute("firstVisit");
if (firstVisit.equals("")) {
session.setAttribute("firstVisit",(new Date()).toString());
firstVisit = "new session"; }

%>
First Visit: <%= firstVisit %>
...
I don't believe that the error is because of the "new Date()" code. It seems to be a more general problem.
Do I have to add some more page import statements ?

Thomas

[darranl]

Show the stack trace, does the NullPointerException originate in your code or outside your code?

[trickal]

Hi Thomas,

you wrote:

(1) String firstVisit = (String) session.getAttribute("firstVisit");
(2) if (firstVisit.equals("")) {
(3) ...
(4) }

If a user is visitting your page the first time, firstVisit is null after the first line. So you're trying to check if null is equal to "" in line 2. This results in a NullPointerException.

Thomas