Error: Cannot find main class in Development/Java

[Xardov]

So i'm following CokeAndCode.com's tutorials on LWJGL 3D games, and I downloaded the source, just to see what the finished game would be like.  I downloaded and installed LWJGL in the correct way, but when trying to compile, I get this error:

Error: Could not find or load main class Development\Java
Java Result: 1
BUILD SUCCESSFUL (total time: 0 seconds)

I am using NetBeans, and strangely, I tested the source in Eclipse, so I don't think it's a problem with the source, but I followed the LWJGL instructions to the letter.

Here is a screenshot of my folder structure. 

[ReBirth]

Make sure your build configuration project acknowledges your main class.

[UprightPath]

What ReBirth said. And make sure that the project you want to run by clicking the arrow is your set as the Main Project.