Home > Diagrams
> Sequence Diagram
Lost/Found Element Creation
In this section, you will describe the concept of the lost/found
and see how to create lost/found element in the Sequence diagram.
This section includes the
- A found message is a message where the receiving event occurrence
is known, but there is no (known) sending event
occurrence. We interpret this to be because the origin of the message
is outside the scope of the description. This may for
example be noise or other activity that we do not want to describe in
detail. The semantics is simply the trace
- A lost message is a message where the sending event occurrence is
known, but there is no receiving event occurrence. We
interpret this to be because the message never reached its destination.
The semantics is simply the trace (sendEvent).
2. Create lost/found element
To create a lost/found element directly in your sequence diagram, click
the icon Add a Return in the
toolbar and drag and drop this element inside the Sequence diagram.
Click on the Add a link Return to connect the
Return with the LifeLine.
Add a name in the Label field and slect
one option (e.g. Return or Throw
Here is the new Return creation which is
used in the create lost/found element concept.
that the Return (e.g. lost/found element) is only a graphical element
and could not be saved in the UML Superstructure Model because this
element doesn't exist in UML 2.2.