How to set header in JSP

thanks for the response.   I am checking now.

I'm not sure how this example is helpful.  I understand what TAS (which interfaces with SiteMinder) is doing in the getUserName method.   My question is how to set a header name of "SM_USER" in the HTTP  REQUEST.     I would like to do so from my JSP but if this isn't possible, I need guidance on how to accomplish this in a Java Servlet that I can call from my JSP.    

I think I can use the response.setHeader("name", "value")

but I'm not sure if this will work.    I'm basically trying to simulate what SiteMinder would do if it was sending a request to TAS (Trusted Authentication Service) but again, I need to do so from a JSP page or a servlet.   My JSP is basically reading a cookie that was set by our SSO (Single Sign On) service.

as far as i am concerned you cannot use "sm_user" header in HttpRequest. sm_user is a predefined header attribute in Siteminder request object and has nothing to do with HttpRequest headers.

You need to achieve this in alternate way like Webservice call....

-Murali*

I can call it anything I want.   It doesn't have to be "sm_user".   I was just doing this so I wouldn't have to write a new class that extends the current HttpUserNameCallback class and looks for my attribute name instead of "sm_user".   I can do this however.   It's no big deal.    

The question is whether or not it's possible to set a custom header in a JSP and then forward the Request object to a different page or URL.   I know that the HttpUserNameCallback class will be called when the TAS URL request is made and it's currently looking for a username value (below).   What can I do if I need to send the userName value in a header to the TAS URL?

 public String getUserName(HttpServletRequest request)
        throws RemoteDataException
    {
        if(useIdentifier)
        {
            String identifierHeaderCheck = request.getHeader(identifierHeaderName);
            if(identifierHeaderCheck != null && identifierHeaderCheck.equals(identifierHeaderValue))
                LOG.debug("Identifier passed security check");
            else
                throw new RemoteDataException("user_not_authenticated_error_label", "The user cannot be authenticated");
        }
        String userName = request.getHeader(userNameHeader);
        if(userName == null)
            userName = request.getRemoteUser();
        LOG.debug("Getting " + userName + " from the request");
        return userName;
    }

Do you think the following article might help?

http://www.experts-exchange.com/Programming/Languages/Java/J2EE/JSP/Q_23915700.html

You cannot add attributes to  the HTTP headers in jsp or servlets. But filters could help to override it.

See this http://www.theserverside.com/discussions/thread.tss?thread_id=41118

So let me ensure I understand, within my JSP, I will still retrieve the cookie value I need but I will make a call to a filter class that will allow me to set a custom HTTP Header and then redirect to the TAS URL.  How will I obtain this value?

Please understand the flow.   Our SSO application will only redirect to a JSP page after authenticating a user and setting a cookie.  It will not pass anything or create a header.  It is up to me within the JSP to obtain the value I need from the cookie and then redirect to the TAS URL with the necessary variable in the HTTP REQUEST HEADER.  Since you're saying I can't do this directly within the JSP, it sounds like I need to create a filter class that is called from my JSP and within this class, I need to set a header and then redirect to the TAS URL.  

Does this sound correct?