This screen shot shows three instances of the ClassDiagramNode example class. Don’t take the contents or the meaning of the links seriously–it just demonstrates what you and what the user could do.
Each ClassDiagramNode has only a single port. It is actually a GoBoxPort so that the links can be positioned evenly on each side of the node.
Each node also holds three GoCollapsibleHandles, shown with two different Styles: GoCollapsibleHandleStyle.PlusMinus (the default) and Chevron.