#Sequence diagram parallel series

Each operand in the frame represents a thread of execution done in parallel. You then break up the frame’s content section into horizontal operands separated by a dashed line. The parallel combination fragment is drawn using a frame, and you place the text “par” in the frame’s namebox. The parallel combination fragment element should be used when creating a sequence diagram that shows parallel processing activities. When the processing time needed to finish portions of a complex task takes longer than previously thought, some systems handle parts of the processing in tandem. Where there is a break combination, which is part of an alternative or a loop, then only the alternative or loop is exited. Once all the messages in the break combination have been sent, the sequence exits without sending any of the remaining messages (e.g., addDebitTransaction).Īn important thing to note about breaks is that they only cause the exiting of an enclosing interaction’s sequence and not necessarily the complete sequence depicted in the diagram. However, in cases where the balance is less than the amount, then the sequence enters the break combination fragment and its messages are sent. If the balance is not less than the amount, the next message sent is the addDebitTransaction message, and the sequence continues as normal. When the sequence gets to the return value “balance,” it checks to see if the balance is less than the amount. The figure below uses a break combination fragment since it treats the balance < amount condition as an exception instead of as an alternative flow. First, a break’s frame has a name box stating “break” instead of “option.” Second, when a break combined fragment’s message is to be executed, the enclosing interaction’s remainder messages will not be executed because the sequence breaks out of the enclosing interaction.īreaks are utilized to model exception handling. The break combined fragment is similar to the option combined fragment. If you do recall, back in the post called – The Basics & the Purpose of Sequence Diagrams ~ Part 2 – there was information on combined fragments known as “alternative,” “option,” and “loop.” While these combined fragments are what most people will utilize the most, there are other combined fragments, such as break and parallel, which a large share of people will find useful. While we did spend some time discussing Gates and its use or relevance to Sequence Diagrams, we now concentrate on just two elements known as Combined fragments.

#Sequence diagram parallel series

We got the final part of this series right here.