Game()
  {
     for(int i = 0; i < targets.length; i++) {
      targets[i] = new ColumnOfBoxes(c, n);
      MouseListener tl = new TargetListener(...);
      targets[i].addMouseListener(tl);
      add(targets[i]);
    }
    add(puck);
    addMouseMotionListener(movePuck);
  }