This week's book giveaway is in the OCAJP 8 forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide and have Edward Finegan & Robert Liguori on-line! See this thread for details.
Not sure if this is the right forum - but here goes.
I'm developing a web app that will be viewed only from a handheld device, via a wireless network. My app worked fine in a test environment, but when I access it on a handheld, one of my objects isn't visible - I get a null-pointer exception when I try to display it. Without going into all the specifics, is there something special I should know about accessing my page & my objects thru a handheld?
I got a HTTP Status 500 error, with a root cause of java.lang.NullPointerException, in the handheld's browser. No error in the Tomcat console on the server side. The browser error message points to a line in the compiled JSP. When I look at that line (or close to it...) it is the first time (on this page) where I'm referencing a method on one of my Objects.
It is hard to say what can be the problem. It can be an encoding or content-type problem. I had once problem when I tried to send POST data without setting proper content-type. Consequently the servlet could not get the parameters from the request and so on.
If you can run that under debugger I think it will be the easiest to catch the problem.
Best regards, Yuri
Joined: May 07, 2001
AACCK!! I just realized I had different versions of both j2sdk & tomcat on my test machine vs the server machine. I reinstalled both & problem's gone <knocks on wood/>