Adding Nodes and Edges

• Objects are more flexible than classes
• new CircleNode(Color.BLACK)
  new CircleNode(Color.WHITE)
• When user inserts new node, the toolbar node is cloned
  Node prototype = node of currently selected toolbar button;
  Node newNode = (Node) prototype.clone();
  Point2D mousePoint = current mouse position;
  graph.add(newNode, mousePoint);
• Example of PROTOTYPE pattern