asked on

Alternate for Cookies and Session variables

Hi,
Both Session Variables and Cookies require client to have cookies enabled on their computer. Is there any alternate which doesn't require cookies enabled and stores session values.

SOLUTION

Mick Barry

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Acton Wang

>>Both Session Variables and Cookies require client to have cookies enabled on their computer

A misconcept here. Actually session variables are stored ONLY in server side and have nothing to do with cookies or url rewriting.

other than that, yes, as objects said , 2 ways to implement session:
1. cookie
2. URL rewriting so called jsessionid

acton

cool_baba

ASKER

>> A misconcept here. Actually session variables are stored ONLY in server side and have nothing to do with cookies or url rewriting.
Its true that session variables are stored only on server side but it needs cookies enabled on client as it use a cookie called SessionID. A bit annoying but that is how it works.
I am going to work on JSessionid I hope it doesn't require cookies enabled on client

Baba

Mick Barry

url rewriting does not use cookies

cool_baba

ASKER

Isn't it something like GET for HTML forms, with limitations on data transfer to the server. If anybody knows ViewState using the JSP.

Mick Barry

basically just involves passing the session id in the query string

ASKER CERTIFIED SOLUTION

colr__

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cool_baba

ASKER

Colr__ I am using firefox. it doesn't allow session variables or use URL rewriting.

colr__

Im using firefox too and Ive never had a problem with setting session variables. The session variabels are not 'allowed' by the browser, it is a function of the J2EE container. If you attemp to use a session variable, and the container detects that the browser wont accept cookies, the container will then use URL rewriiting. This all happens transparently to the browser.

As far as how URL rewriting works, I dont know that - Ive never came across a situation where Ive had to delve into the implementation of it - all you need to know is that session variables will work, how it does it is not important.

So, using session variables, it doesnt matter that your breowser may nor may not accept cookies, as if it doesnt, then the container will automatically switch to URL rewriting.

colr__

cool_baba

ASKER

Use this code in mozilla firefox, with cookies disabled.

<HTML>
<BODY>
<FORM METHOD=POST ACTION="SaveName.jsp">
What's your name? <INPUT TYPE=TEXT NAME=username SIZE=20>
<P><INPUT TYPE=SUBMIT>
</FORM>
</BODY>
</HTML>

code for SaveName.jsp

<%
String name = request.getParameter( "username" );
session.setAttribute( "theName", name );
%>
<HTML>
<BODY>
<A HREF="NextPage.jsp">Continue</A>
</BODY>
</HTML>

code for NextPage.jsp

<HTML>
<BODY>
Hello, <%= session.getAttribute( "theName" ) %>
</BODY>
</HTML>

I have tried it in netscape as well .. if you don't allow cookies value is always null (exception internet explorer)

Thanks for your time and concern Colr__

colr__

Very strange, I've never seen this before.

Can you confirm when using FF and netscape that the SaveName.jsp URL defenetaly has the value set in its URL? For example it should look like this:

SaveName.jsp?username=colr__

Im just wondering if the lack of quotation marks around the html input's are confusing FF and Netscape??

colr__

cool_baba

ASKER

>>Im just wondering if the lack of quotation marks around the html input's are confusing FF and Netscape??
I just didn't understand it. could you modify the code and write it here.

>>Can you confirm when using FF and netscape that the SaveName.jsp URL defenetaly has the value set in its URL? For example it should look like this:
>>SaveName.jsp?username=colr__

It doesn't show username in url ..

Syed

cool_baba

ASKER

Opera doesn't support either ..

colr__

ok, if it doesnt show the username in the url, then the username is not being passed correctly to SaveName.jsp in all but IE.

Try modifying your first html page this:

<HTML>
<BODY>
<FORM METHOD="POST" ACTION="SaveName.jsp">
What's your name? <INPUT TYPE="TEXT" NAME="username" SIZE=20>
<P><INPUT TYPE="SUBMIT">
</FORM>
</BODY>
</HTML>

colr__

cool_baba

ASKER

still not working..

colr__

Ive just realised, your using post,. so you wouldnt see the variabels in the URL of SaveName.jsp. Try changing the methof type to GET and see if the URL is showing the variables in erach of the browsers:

<FORM METHOD="GET" ACTION="SaveName.jsp">

should result in the URL:

SaveName.jsp?username=colr__

colr__

cool_baba

ASKER

yes, variable value is transferred to second page. I mean using GET shows result as: SaveName.jsp?username=colr__

colr__

One last test - change SaveName.jsp to the following

<HTML>
<BODY>
Hello, <%= session.getAttribute( "username" ) %>
</BODY>
</HTML>

Let me know if this wokr son all brosers. Im on a mission now...

colr__

cool_baba

ASKER

Doesn't work for GET or POST. I don't thnk we can access GET or POST variables on page other than target page.

colr__

Sorry, im an idiot, its suppoed to be this:

<HTML>
<BODY>
Hello, <%= request.getParameter( "username" ) %>
</BODY>
</HTML>

colr__

cool_baba

ASKER

Yes it works .. So variables are accessable on second page.
it works for all browsers.

cool_baba

ASKER

helloo Colr__ are u still working on your mission ?

cool_baba

ASKER

Here is how i solved my problem..
source : http://home.earthlink.net/~alxdark/software/wcd-guide/ch05s03.html

If the user has disabled cookies then session variables doesn't work as client browser doesn't allow to set cookie called SESSIONID, which carries the session id information for the server. To overcome this problem urlrewriting is used by every URL written out by a servlet or JSP page should be run through the

public String HttpServletResponse.encodeURL( String url );
public String HttpServletResponse.encodeRedirectURL( String url );

methods in the servlet API. first one (encodeURL) just attaches the sessionid with the url, second (encodeRedirectURL) rewrites url if cookies are disabled otherwise, sessionid cookie is stored on computer.

Code i posted above should be changed like this:

<HTML>
<BODY>
<FORM METHOD=POST ACTION="SaveName.jsp">
What's your name? <INPUT TYPE=TEXT NAME=username SIZE=20>
<P><INPUT TYPE=SUBMIT>
</FORM>
</BODY>
</HTML>

code for SaveName.jsp

<%
String name = request.getParameter( "username" );
session.setAttribute( "theName", name );
%>
<HTML>
<BODY>

<A HREF="<%= response.encodeRedirectURL("NextPage.jsp") %>">Continue</A> // CHANGE IN CODE
</BODY>
</HTML>

code for NextPage.jsp

<HTML>
<BODY>
Hello, <%= session.getAttribute( "theName" ) %>
</BODY>
</HTML>