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This means that the action cannot access the object itself. The object token plays
the role of a control token. Control pins are often not shown in the diagram.
Figure 2.95 shows a control pin for better understanding. If you want to have a
model that is 100 percent formally correct you sometimes have to use such modeling
tricks. Normally the information is only in the model and not in the diagram.
We used a Success pattern in Figure 2.58 .
The Termination pattern helps activities that have a decision to take after each
action to check whether or not it is necessary to terminate ( Figure 2.96 ). For example,
these can be fl ows that can be terminated by an event, such as an emergency-off
event of a machine, or a termination due to expiry of a given time interval.
The region concerned is modeled with an interruptible activity region all
around it, which can be exited by a termination event ( Figure 2.97 ). If the entire
fl ow, i.e., the complete activity, is to be terminated by the event, then the interruptible
activity region is omitted ( Figure 2.


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