What is an Activity Diagram in UML?

What is an activity diagram in UML?

Activity diagrams are easy to create and understand. They're simply flowcharts with a different system of notation. Like flowcharts, all shapes in an activity diagram are represented by standardized symbols.

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What is an Activity Diagram in UML?

The Unified Modeling Language has several subsets of diagrams that it can model, including structure diagrams, interaction diagrams, and behavior diagrams. Activity diagrams are a subset of the latter. Along with use case and state machine diagrams, they're used to describe business activities and software systems' functionality. You'll use a set of specialized symbols—including those for starting, ending, merging, or receiving steps in the flow—to build an activity diagram.

Stakeholders have many issues to manage, so it's important to communicate with clarity and brevity. Activity diagrams help people on the business and development sides of an organization come together.

What is an activity diagram in UML?

Use Cases for Activity Diagram

Activity diagrams have a number of benefits for any organization. Try using an activity diagram to:

  • Demonstrate the logic of an algorithm.
  • Describe the steps performed in a UML use case.
  • Illustrate a business process or workflow between users and the system.
  • Simplify and improve any process by clarifying complicated use cases.
  • Model software architecture elements, such as method, function, and operation.

ACTIVITY DIAGRAM COMPONENTS

To answer the question of "What is an activity diagram in UML?", you should first understand its makeup. Some of the most common components of an activity diagram include:

  • Actions - a step in the activity wherein the users or software perform a given task. In Lucidchart, this is symbolized with a round-edged rectangle.
  • Decision node - a conditional branch in the flow that is represented with a diamond. It includes a single input and two or more outputs.
  • Control flows - this is another name for the connectors that show the flow between steps in the diagram.
  • Start node - symbolizes the beginning of the activity. This is represented with a black circle.
  • End node - represents the final step in the activity. It's modeled with an outlined black circle.
What is an activity diagram in UML?

Lucidchart offers an extensive set of UML shapes and connectors. Use our tool to craft activity diagrams, sequence diagrams, component diagrams, and more. We make it simple to collaborate with others and share online, so try it today!

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