How do you make an structured cycle for task repetition?
Use the loop symbol in a collapsed sub-process until the decision activity inside gives a positive outcome
How to make parallel repetition?
With a multi-instance activity (An activity (task or sub-process) that is
executed multiple times concurrently) with a completion condition as an annotation.
Symbol: III (three small vertical lines at the bottom)
How do an uncontrolled repetition is modeled?
With an Ad hoc sub-process (One or more activities that may not occur at all or may occur multiple times in no specific order (i.e., are uncontrolled) until a condition is met) with a completion condition as a text annotation
Symbol: ~ (sub-process box with tilde symbol at the bottom)
Make the chart of the main types of handling events
Check notes
What are the 8 types of events?
Untyped
Message
Temporal
Start (Signal how/when process instances start)
Intermediate (Occur during a process)
End (Signal when process instances complete)
Catching (events that catch a trigger, typically originating from outside the process)
Throwing (events that throw a trigger
from within the process
What are racing events (event-based XOR split? Draw an example and symbol
External choice that is determined by the process environment; choice is delayed until an event happens; i.e., event occurring first (à “race”) will determine how execution proceeds.
For drawing check notes
What are exceptions
Events that deviate a process from its normal course (business or technology faults)
How do we abort a process? What’s the symbol used?
With an end terminate event:
It causes the abnormal and immediate
termination of a process instance.
Destroys all tokens of this instance
Symbol: end event with full circle inside
What are the 3 types of exceptions and with which type of events is each one handled?
- Internal: something goes wrong inside an activity, whose execution must thus be interrupted -> Handled with error event
- External: something goes wrong outside the process, and the execution
of the current activity must be interrupted -> Handled with message event - Timeouts: an activity takes too long and must be interrupted -> Handled with timer event
What are the symbols of the two error events in internal exceptions?
- Throwing: with full lightning
- Catching: with empty lightning. Triggers and exception-handling routine
what are the symbols of external exceptions?
- Message event (catching intermediate event) with empty envelope, triggers recovering procedure
What is the symbol used for activity timeouts?
Timer event: Catching intermediate event (with empty clock)
What are non-interrupting events? what’s the symbol?
Are events that occur during an activity but they don’t interrupt the process, they trigger parallel processes.
Non-interrupting event: Catching message event (with dashed double border)
What are the signal events? Which are the types?
A signal event has a source but no specific target (i.e., can be caught multiple times); in contrast, a message event has both a specific source and a specific target.
- Throwing end event (with full triangle)
- Catching intermediate event (with empty triangle)
What’s an event sub-process? What’s the symbol?
They can model events that occur during the execution of the whole process (i.e., at any time during the process)*
symbol: (dotted rectangle with rounded corners)
What’s an activity compensation?
It undoes one or more steps based on an exception. It has two types of events:
- throwing end event (fill rewind symbol)
- catching intermediate event (empty rewind symbol).
It comes with a compensation activity
How do we create a model that considers exceptions
- Model the simple “sunny day” scenario
- Think of all possible situations
that can go wrong - For each of these exceptions:
(a) Internal vs. external cause?
(b) Abortion vs. Recovery?
(c) Need for compensation?
What are business rules and how can they be captured via BPMN?
It implements an organizational policy or practice. They can be captured via decisions activities, conditions or conditional events (catching start event with lined paged symbol)
What’s the difference between conditions and conditional events?
- A condition is tested only once, whereas
- A conditional event is tested until the associated rule is satisfied.
