BPMN Notation System
Let's take a closer look.
Main components
Events
Events in BPMN are represented as circles and serve to designate various situations that occur in the process and affect its course. They can be of three types: initial, intermediate And final.
Initial Events start the process. They can be activated by external triggers, such as receiving a message or the arrival of a certain time.
Intermediate events occur during the execution of a process and can be either intercepting or initiating actions.
End Events indicate the completion of a process and may indicate successful or exceptional completion of the process
Activities
Activities represent the work that needs to be done within a process. They are displayed as rectangles with rounded corners and can be of two types: tasks and subprocesses. Tasks are atomic actions that cannot be further broken down into smaller steps. Subprocesses are more complex activities that can contain other tasks or subprocesses, allowing the process to be detailed at a lower level.
Gateways
Gateways in BPMN are used to manage branches and merges in a process flow and are depicted as diamonds. They determine which flow paths will be executed depending on certain conditions being met. There are different types of gateways such as exclusive, enabling, event-based gateway And parallel.
Exclusion Gateway used to create alternative paths in a process. At any given time, only one of the possible paths can be chosen. This gate evaluates the conditions on the output streams and selects the stream whose condition evaluates to true. If the conditions are not met, a default thread can be chosen to avoid blocking the process.
Enable gateway allows one or more process paths to be activated simultaneously based on an assessment of conditions. This type of gate requires that all activated incoming branches be completed before the process can continue.
Parallel gateway used to execute multiple process paths simultaneously. It does not evaluate any conditions and simultaneously activates all outgoing flows. When merging, the parallel gateway waits for all incoming threads to complete before the process can continue.
Event-based gateway used to control the flow of a process based on events rather than conditions. The process waits on the gateway until one of the expected events occurs, after which the corresponding thread is activated. This gateway can be used, for example, to wait for a payment to arrive from a client
These elements are connected to each other using sequential streams, which show the order in which activities are executed, and thread messages, which indicate the exchange of information between various participants in the process.
Artifacts
Artifacts are used to add extra. information on diagrams. They do not directly affect the flow of the process, but provide important contextual information that helps participants in the process better understand its details and relationships. In short, these are comments.
There are three types of artifacts:
Data Objects show what data is needed or produced in the process. These artifacts can represent data that needs to be collected or that is created as a result of activities. They can be used to indicate that certain data should be available before a task begins or stored after it has completed.
Groups are visual containers that can be used to group together elements that share common characteristics without affecting the flow of a process.
Text annotations provide the ability to add comments directly to the diagram.
BPMN Example
Tips for creating a chart
Keep your diagrams simple. Use only the necessary symbols and elements to convey the process, avoiding unnecessary details that may complicate understanding.
Use consistent symbols and notations throughout your models to ensure clarity.
Use divisions to indicate responsibilities for different parts of the process.
BPMN is not a one-time task. Review and improve your processes regularly, using data to identify areas for improvement.
One of the most common mistakes is using different names for the same elements or processes.
Diagrams that are too detailed can be confusing and distract from the overall purpose of the process. It is better to stay at a level sufficient to understand and analyze the process.
It is important to correctly use gateways to control process flows, choosing the appropriate gateway type depending on the conditions and rules of the process.
In conclusion, I remind you about open lessons at OTUS, which will be held in May:
