session

[Aditi agarwal]

i am developing a web application using struts 1.3

my heirarchy is like this

userlogin.jsp calls admin.jsp in which one of the frame call left.jsp which has a link changepassword.jsp

i have define a sesion on my userlogin.jsp

<%
session = request.getSession(false);
String user= (String)session.getAttribute("username");
session.setAttribute("username",user);
%>

in my all pages i have call

<%String username=request.getParameter("un"); %>
<%=un%>

but this is printing null i have also defined these lines in my all jsp but still it is giving me null

please help me out with sessions if there is any error then also please help me because i donot know much about session

thank you

[Shailesh Narkhede]

Hi Aditi,

Are you appending "un" parameter and its value in every time while submitting form.
bye the way you are putting username in session attribute with name "username" nad you are trying to get it from request paramter you can get it from session.

HTH

[Aditi agarwal]

thank you Shailesh for your reply

but please help me more by telling me how to do it thru sessions only as i am new to it & i also cannot foun it on google

i am not appneding un parameter again & again

thank you
looking forward for your answer

[Shailesh Narkhede]

Hi Aditi,

you can get session object from request you can see HttpServletRequest Object help for that.
After getting session you can getAttribute from session and show it on each JSP.

[debraj mallick]

Hi Aditi,

if you use

session.setAttribute("username",user); 

then you can get the username as

session.getAttribute("username");

in all jsp pages, but you have used
String username=request.getParameter("username");
there is difference between request and session

I think you understand what i mean to say........

[debraj mallick]

hi,

i hope this link will help you to understand better (some examples are there)
http://www.java2s.com/Code/Java/JSP/Session.htm

[Aditi agarwal]

thanks once agin debraj you again saved me
now i understand what you are saying


thanks to you too Shailesh you have also helped me alot

[Aditi agarwal]

hey debraj i have tried
String user= session.getattribute(valid);

but its also giving me null please tell what to do
thank you

[debraj mallick]

hi,
String user= session.getattribute(valid);
it should be

String user= session.getAttribute("valid");  

[Aditi agarwal]

hi debraj

i have written same i have written it wrong here only i am sorry for that

String user = (String) session.getAttribute("valid");
if(user==null)return mapping.findForward("failure");

& its taking nnull value only not showing me success

what should i do

[debraj mallick]

hi,

i didn't find anything wrong

HttpSession session = request.getSession(); 
String user = (String) session.getAttribute("valid");
if( user == null)return mapping.findForward("failure");

[Joe Ess]

The code in a JSP is run before the JSP is displayed on the browser. If you are expecting to capture the username from the JSP where a user enters it, you will be disappointed. What you want to do is submit the login form to an action and let the action set the username in the session.
I recommend that you spend some time working through the many Struts tutorials (see our Struts FAQ before trying your own web app. A little research up front will save you many headaches down the road.
And use Struts 2 if you can help it.

[Aditi agarwal]

thanks debraj

thanks joe for telling me that i should set session in my action form not in my jsp page thank you once again

[Aditi agarwal]

hey joe

now i have set my userLoginAction

HttpSession session = request.getSession(false);
		String user1=userLoginForm.getUsername().trim();
		String user= (String)session.getAttribute(user1);
		session.setAttribute("user",user);

& my changepasswd.jsp as

<%String username = (String)session.getAttribute("valid"); %>

& my changepasswdAction as

HttpSession session = request.getSession();
		String user = (String) session.getAttribute("valid");
		if(user==null)return mapping.findForward("failure");

One more thing i would kike to ask you that after userlogin.jsp->admin.jsp->left.jsp->changepasswd.jsp is a link with target set on right.jsp

do i need to start a session in all in betweeen files too or its not neccessary

thank you

[Joe Ess]

HttpSession session = request.getSession(false);
String user1=userLoginForm.getUsername().trim();
String user= (String)session.getAttribute(user1);
session.setAttribute("user",user);

Can you explain what each of those lines in your code does? I don't think they do what you think they do.
A session is "started" once. You only need to reference it when you need to get/set an attribute.

[Aditi agarwal]

tually firstly a session is started

then the

String user1=userLoginForm.getUsername().trim();
stores name of user who is logged in from my userloginform


String user= (String)session.getAttribute(user1);

assigsn user a value


session.setAttribute("user",user);
this value is to be used i think it does this
if i am not mistaking it

if any error please guide me to correct way

thanks

[Joe Ess]

Aditi agarwal wrote:
String user= (String)session.getAttribute(user1);

assigsn user a value

What value do you expect here?

[Aditi agarwal]

hey joe in user i need th value of person who is logged in fom my page userlogin.jsp whose form is userloginform

[Joe Ess]

Isn't that what the previous line does?

String user1=userLoginForm.getUsername().trim(); 

[Aditi agarwal]

thats what i have written but you said it might be correct or ....

so i just ask you then tell me

you told me on jsp we cant track the user so on action i have written these lines but still me getting null can you just help me why still its null

code on action page

HttpSession session = request.getSession(false);  
String user1=userLoginForm.getUsername().trim();  
String user= (String)session.getAttribute(user1);  
session.setAttribute("user",user);  

please help me

thank you

[Aditi agarwal]

hey one more thing i noticed my code

HttpSession session = request.getSession(false);    
String user1=userLoginForm.getUsername().trim();    
String user= (String)session.getAttribute(user1);    
session.setAttribute("user",user); 

my user1 is printing 'admin' which is my user but my user is printing null

help me joe

thank you

[Aditi agarwal]

hey some body please help me i need it yr

please

[Joe Ess]

Please be patient. We are all volunteers here, answering questions in our free time.

You say:

my user1 is printing 'admin' which is my user but my user is printing null

So doesn't the variable "user1" contain what you are looking for?

Why do you attempt to retrieve something out of the session before you set it in the session?

# String user= (String)session.getAttribute(user1);      
# session.setAttribute("user",user);  

Again, I will ask you to have a look at our FAQ and go through some tutorials (perhaps even the Java Tutorial). It is much easier to first gain an understanding of the language and framework first than it is to cobble together an application without understanding either.

[krishna bala]

use the following code in your action class

String userName = <yourform reference variable>.getUserName();
session.setAttribute("username",userName) ;


where ever you want username from session, just use the following code

String userName = (String)session.getAttribute("username");

note : donot create session object on jsp page, because session object is an implecit object.

[Aditi agarwal]

thank you joe & krishna

& sorry too joe for being impatient actually i need it bcause only one module of my project is left behind all is complete else so i need it fast

lemme try your ideas