Similar to pins, an activity can have input and output parameters, except on
the activity level. Input and output parameters are denoted as rectangles on top
of the activity ??™ s encompassing rectangle ( Figure 2.63 ). Inside the rectangle of a
parameter there is its name, which normally corresponds to the parameter ??™ s type.
An incoming activity parameter also assumes the function of an initial node. This
is the point where a fl ow begins as soon as the activity has been invoked. In contrast,
however, an outgoing activity parameter does not have the same function as
an activity fi nal node. It is the point where the fl ow that placed an object in the
parameter node ends. This ends the entire activity only provided that this fl ow
was the last within that activity. This means that the semantics is similar to that of
fl ow fi nal nodes.
You can see that both activity parameters and initial and fi nal nodes are modeled
in Figure 2.63 . Invoking this activity causes three fl ows to start. The fl ows
with the customer and car objects are initially blocked, because the target??”the
step request usage right ??”is not yet ready to accept these objects.
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