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Question

Consider the following Activity Diagram :

First of all the activity a22 is confusing me through this configuration .If we need to list all the possible activity sequences that can take place in this activity diagram. My answer is as follows :

Sequence one : a11 ; parallel combination of a22 , a33 and a44 ;a77.

Sequence two : a11 ;parallel combination of a22 , a33 and a44 ; parallel combination of a55 and a66.

Is this a right answer ?

Answer 1

Almost.

The first answer is ambiguous. It's

a11 followed by a22 running in parallel to [ a33 || a44 followed by a77 ].

That finalizes when a77 is done. a22 can't reach the termination since it's stuck at the synch bar.

The second is also incorrect.

a11 followed by a22 running in parallel to [ a33 || a44 followed by a55 || a66 ]

So it finalizes when a22, a55 and a66 have finished. Which ever takes longest.