Problem in Game Engine

I Have this problem in my game engine where I am trying to create a double buffering image and it keeps saying null. I have tryed to debug but still cant get this to work. I only have today to get it to work so I would love it if you fix it thanks Toby.

Code here https://www.dropbox.com/s/25wm2wcaz77awkg/Eclispe%20Workspace.zip