There IS a difference. In part 2, you should use
if (db != null)
instead of
if (db.empty())
Hope this helps
-----Original Message-----
From: Daniel Liu [mailto:[EMAIL PROTECTED]]
Sent: Friday, February 16, 2001 9:45 AM
To: [EMAIL PROTECTED]
Subject: Problem: share objects
I have some trouble in using the methods: getAttribute and
setAttribute.
A code segment of the method init() in my servlet as below:
/**************************************************************
ServletContext sc = getServletContext();
// Part 1
String test = (String) sc.getAttribute("test");
if (test == null ) {
test = new String("test");
sc.setAttribute("test", test);
}
// Part 2
ShoppingCartDB sdb =
(ShoppingCartDB) sc.getAttribute("ShoppingCartDB");
if (db.empty()) {
sdb = new ShoppingCartDB();
sc.setAttribute("ShoppingCartDB", sdb);
}
//.....
************************************************************/
the program throw an exception when execute Part 2. I do not see
any difference between Part 1 and Part 2.
Please help. Thanks.
----------------------
Daniel Liu
MONTAGE eIntegration(tm) Inc.
Tel: (613) 820-0080 x500
[EMAIL PROTECTED]
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