UML Modeling Techniques > Class modeling > Interfaces > Adding an existing interface to a diagram
  
Adding an existing interface to a diagram
You typically show an Interface on a Class Diagram or Composite Structure Diagram as a lollipop or cup, but you can also show an Interface on a diagram as an Interface symbol.
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If an Interface is already linked to a Class, Data Type, Interface, Signal or Interface that appears on a Class Diagram, you can use the Populate Interfaces command to add the Interface to the diagram.
To add a provided interface as a lollipop:
1. On the Class Diagram or the Structure Diagram toolbar, click the Provided Interface button.
2. Click the Class, Data Type, Signal, Part or Port on which the Interface is dependent.
3. Using the right mouse button, double-click where you want to add the Interface.
4. From the Select Object dialog, select the Interface you want to add to the diagram.
5. Click OK.
Modeler adds the Interface to the diagram as a lollipop. If there is a valid interface realization Dependency in the Model, Modeler uses that Dependency. If there is not a valid interface realization Dependency in the Model, Modeler creates a new Dependency.
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You can double-click in free space, and then right-click the Class, Data Type, Signal, Part or Port on which the Interface is dependent.
To add a required interface as a cup:
1. On the Class Diagram or Structure Diagram toolbar, click the Required Interface button.
2. Click the Class, Data Type, Signal, Part or Port on which the Interface is dependent.
3. Using the right mouse button, double-click where you want to add the Interface.
4. From the Select Object dialog, select the Interface you want to add to the diagram.
5. Click OK.
Modeler adds the Interface to the diagram as a cup. If there is a valid uses Dependency in the Model, Modeler uses that Dependency. If there is not a valid uses Dependency in the Model, Modeler creates a new Dependency.
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You can double-click in free space, and then right-click the Class, Data Type, Interface, Signal, Part or Port on which the Interface is dependent.
To add an interface as an interface symbol:
Drag the Interface from the appropriate pane to the diagram.