code: public Icon<Connector<T>> getOrCreateIcon()
     {
        Node node = childNode.getOrCreate("icon");
        Icon<Connector<T>> icon = new IconImpl<Connector<T>>(this, "icon", childNode, node);
        return icon;
     }
docs: If not already created, a new <code>icon</code> element with the given value will be created.
  Otherwise, the existing <code>icon</code> element will be returned.
  @return  a new or existing instance of <code>Icon<Connector<T>></code>