Well I understand completely what is happening now. I did not really think that Java would obliterate synchronization. Thanks for the clarification frob!!!
You really want to AVOID MULTITHREADING inside your engine until you have already mastered many other areas of game development.
I am kind of thinking ahead when in the future I would have a scene with many objects appearing and dissapearing or changing shapes. For things like buffers in that instance multithreading would be a great boost (think OpenCL oh noes). I also think that starting to thread simple code is much easier than threading at the end where u can miss something and might have to debug... for a while : )
Plus I am just doing this for fun to learn more about Java and graphics.
Again many thanks for your replies and have a great day!