Split behavior into a set of parallel or concurrent flows of activities (or actions)īring back together with a set of parallel or concurrent flows of activities (or actions).Ī way to group activities performed by the same actor on an activity diagram or to group activities in a single threadĭescribe High-Level Interactions between a System and External Systems Represent a test condition to ensure that the control flow or object flow only goes down one pathīring back together with different decision paths that were created using a decision-node. Represent an object that is connected to a set of Object Flows Stop all control flows and object flows in an activity (or action) Portrays the beginning of a set of actions or activities Show the flow of an object from one activity (or action) to another activity (or action). In addition, an activity diagram is also a common technique is to dissect a single-use case specification either a text specification or an activity diagram, and subsequently for creating a set of sequence diagrams, one per path (scenario).Ī basic activity diagram – flowchart likeĪctivity Diagram Notation Summary Notation Description.Activity diagrams are often used to create graphical use case specifications which tend to be more concise and less ambiguous than the traditional text form of a use case specification.Activity diagrams are commonly used as an analysis tool to understand and express the desired behavior of a system.Common usages of an activity diagram in SysML includes: Thus, it is typically used to specify behavior, with a focus on the flow of control and the transformation of inputs into outputs through a sequence of actions. An activity diagram is particularly good at expressing the flow of objects-matter, energy, or data-through a behavior, with a focus on how the objects can be accessed and modified in the execution of that behavior during system operation. However, each one has strengths and weaknesses that make it more or less appropriate based on the needs of your target audience.Īctivity diagrams can express complex control logic better than sequence diagrams and state machine diagrams. All three can express sequential and concurrent behaviors and event occurrences over time. In SysML, an activity diagram is inherited from UML with some minor modifications.Īctivity diagrams, sequence diagrams, and state machine diagrams are the three options that SysML offers you to specify system behavior.

An activity diagram is a kind of behavior diagram it’s a dynamic view of the system that expresses sequences of behaviors and event occurrences over time.

Sysml sequence diagram