Whattha?! - java.lang.classnotfoundexception

Newbie & Debugging Questions
#1

I’m using NetBeans IDE.

I just saved my latest version, accedentaly clicked ‘Build and Clean’ insted of ‘Run’ and now i’m getting the following error:

run:
Exception in thread "main" java.lang.NoClassDefFoundError: EntitySystem/Entity
        at isogameengine_01.Main.main(Main.java:21)
Caused by: java.lang.ClassNotFoundException: EntitySystem.Entity
        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
        ... 1 more
Java Result: 1
BUILD SUCCESSFUL (total time: 2 seconds)

To the best of my knowlage, I have not changed ANYTHING apart from accedentaly clicking the ‘Build and Clean’ button…

can anyone tell me what is this, why might it have happened and how could I fix it?

#2

I have strange behaviour with Netbeans recently… ClassNotFound… Class that doesn’t overwrite abstract method when it does…

For one project, I change compilation from Java 1.5 to Java 1.6 and it “solved” the problem. For another, I disable the compile on change…

There is really something strange :-\

#3

Nice one ;D I just turned off ‘Compile on Save’ and it works again!

… that is well weird.

Does anyone have any ideas as to what might be the actual issue? I’m allways a bit woried when something weird happens and I cant find an explenation. I always wonder what else is going to come out of the woodwork…