Occasional Blank Page In Browser When Requesting JSP

[thorntond]

I am having a problem with a JSP page occasionally showing up blank in the browser. When I do a view source on a blank page from the browser, all the html is there and it's no different than the html when the page doesn't come up blank. I've tested with both Jetty and Tomcat and Netscape and IE and I can get it to happen with all combinations. It happens most often when a jsp page is being loaded into a browser for the first time. My initial guess is that it's some kind of timing issue with the browser.
I'm hoping somebody might have a quick solution to this problem before I start testing the offensive jsp by stripping it down line by line.

I've reproduced this problem with Jboss 3.0 beta/jetty and JBoss 3.0 beta/Tomcat and JBoss 3.0 beta 2 (built today)/jetty. Using Netscape 6.2 and IE 5.5 & 6. OS is Linux.

Danny

[jules_gosnell]

If the webcontainer and browser make no difference then I guess the only constant is your code !

Jules

[jules_gosnell]

One more thought....

When you request to view the source in your browser, it may be going back to the JSP again. Try using something else (the 'get' function in Ant), or telnet to REALLY see what your JSP is kicking out.

Jules

[thorntond]

After hooking a packet sniffer up, I found out a little more about the problem. The problem starts with a server response of http error 302 Moved temporarily. This in itself is ok because I'm reguesting the welcome page. The server redirects from http://www.myapp.com/webcontext to http://www.myapp.com/webcontext/WelcomePage.jsp. When the welcome page makes a requests for the cookies after the redirect that causes the blank page. The offending line of code in the welcome page jsp is:
Cookie[] cookies = request.getCookies();
I'm still not sure how to get the read cookies to work though.

Danny

[jules_gosnell]

You want to try this one on [e-mail].

Someone is sure to help you out.

Jules

[thorntond]

I made two modifications to my jsp and I haven't had this problem since. The first thing I did was add the <% page language="java" %> to the top of the page and the second was to check cookies for a null value. The browsers I tested did have cookies turned on. When the problem was occurring, I did not get any errors in the output log.