java - ArrayList that contains circles that move -

public class second extends jpanel implements actionlistener {    arraylist<ellipse2d.double> circles = new arraylist<ellipse2d.double>();   timer t = new timer(5, this);   double x=0, y=0, velx=1, vely=1;       circles.add(new ellipse2d.double(x,y,10,10));    public void paintcomponent(graphics g) {     super.paintcomponent(g);     graphics2d g2 = (graphics2d) g;     for(ellipse2d.double k : circles){         g2.draw(k);     }     g2.fill(k);     t.start();   } }  public void actionperformed(actionevent e) {   if (x < 0 || x > 560) {     velx = -velx;   }   if (y <0 || y >360){     vely = -vely;   }   //x+= velx;   y += vely;   repaint(); } 

i tried doing didnt work know how draw them , make them move think problem initializing arraylist

error: multiple markers @ line - syntax error on token "add", = expected after token - syntax error on token(s), misplaced construct(s) error add circle

you can execute add method inside method. should move part:

circles.add(new ellipse2d.double(x,y,10,10)); 

to method.