As the title says I have NPE error. It happens on line:
while (getWidth() > bowl.getX()+10) {
If I remove it, it shows it happens on nex
Like most people already mentioned you are shadowing your bowl variable.
GOval bowl = new GOval(10,10);
should be replaced with
bowl = new GOval(10,10);
You can configure eclipse that he gives you a warning when you are doing this. In the preferences you have a dedicated part for this under java -> compiler -> errors/warnings