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setBackground(Color.black);
int c1=(int)(255*Math.random());
int c2=(int)(255*Math.random());
int c3=(int)(255*Math.random());
Color micolor=new Color(c1,c2,c3);
g.setColor(micolor);
g.fillOval(x1,y1,20,20);
x1 = (int)(Math.random()*(getSize().width-20));
y1 = (int)(Math.random()*(getSize().height-
20));
}
public void stop() {
if (runner != null) {
runner = null;
}
}
public void run() {
Thread thisThread = Thread.currentThread();
while (runner == thisThread ) {
for(int i=1; i