In sequence diagrams, you can reference an interaction from within the body of another interaction. This reference is called an interaction occurrence. You can then reuse the definitions in an interaction to abstract and simplify your model. You can add and modify interaction occurrences in sequence diagrams.
Creating interaction occurrences
In sequence diagrams, you can create an interaction occurrence, which appears in a frame with a ref heading, by creating a new interaction, specifying a new unspecified occurrence, or selecting an existing interaction. To open the referenced interaction, double-click the interaction occurrence. If you delete an interaction occurrence, the referenced interaction remains in the model.Moving interaction fragments
In sequence diagrams, you can move the position and change the order of an interaction fragment, which includes combined fragments and interaction occurrences.Resizing interaction fragments
In sequence diagrams, you can horizontally resize any interaction fragment, and you can vertically resize a combined fragment.Adding and removing covered lifelines in interaction fragments
In sequence diagrams, you can add and remove lifelines that are covered by an interaction fragment, which includes combined fragments and interaction occurrences. When you remove a covered lifeline in a combined fragment, all messages and interaction fragments that were contained in the combined fragment and were covered by the lifeline are also deleted.
Parent topic: Modeling interactions by using sequence diagrams
Related concepts
Sequence diagrams
Interaction frames
Interaction occurrences