Hi,
I am running wls6.1 on a Red hat box.
From my ejb, using some helper classes, i am trying to create the image of a bar chart( ofcourse thru awt ).
But at times this throws an exception
java.lang.NoClassDefFoundError: sun/awt/X11GraphicsEnvironment

I have set the DISPLAY parameter properly.. but this problem recurs ..!!!
from a lot of discussion forums i learned that this is a common issue on serverside java under linux.... but nobody had susggested a solution!
any thoughts or similar experiance??
pls answer.

I recently had this exact same problem.

What happens it the first time you run the app using the awt classes, you get a java.lang.InternalError saying it can't connect to the X server using the specified display variable.

After that, you get NoClassDefFoundErrors as you mentioned.

I solved this by doing two things:

1. Installing a Virtual Frame Buffer.
2. Setting my Display Variable to the IP address of the host I am running on.

I just went to RPMFind.net and found the Virtual Frame Buffer RPM for my RedHat 7.2 distribution. Then I installed it. Next, I set the DISPLAy variable to the IP address of the machine the Web App was running on. Then, I started the Virtual Frame Buffer using the command:

/usr/X11R6/bin/Xvfb :0.0 -screen 0.0 1152x900x8 &

Finally, I restarted the web container.

As a side note, it is interesting that you posted this problem because I just encountered and fixed this problem yesterday . . . Spooky kind of.

Dave Costakos

Thanks Man! ... it helped!
btw, What an accidental coincidence of the incidents!!!!

Thanks Dave, this solved my hours of frustration too.

Clinton Lee