One novel feature of the composition GUI is that it allows application composition even before the components are actually instantiated. Here we demonstrate a connection being made (this is done by dragging the mouse between ports) between uninstantiated components. The composition GUI maintains a graph of the application and can make real connections at a later time. Note also that connections are allowed only between compatible ports, which are highlighted for the user. All port information including their types comes from the component XML information.
