Activity Diagram - Decision Notation

This section describes the Decision Notation used in a UML Activity Diagram. A Decision Notation represents a decision action that decides which action path to take next based on certain conditions.

A Decision Notations is a graphical notation used in a UML Activity Diagram to represent a decision action that evaluates certain conditions and decides which action path to continue the execution.

A Decision Notation is drawn as a small diamond shape with one incoming control flow and multiple outgoing control flows. Each outgoing control flow should be labeled with the condition that leads to this flow. For example, the decision action performed after the "Receive Order" action to check the stock can be drawn as a Decision Notation in a UML activity diagram as shown below:
UML Notation Shape - Decision

Last update: 2014.

Table of Contents

 About This UML Tutorial Book

 Introduction of UML (Unified Model Language)

 UML Class Diagram and Notations

UML Activity Diagram and Notations

 What Is an Activity Diagram?

 Activity Diagram - Action Notation

 Activity Diagram - Control Flow Notation

 Activity Diagram - Start and Final Notations

Activity Diagram - Decision Notation

 Activity Diagram - Merge Notation

 Activity Diagram - Fork Notation

 Activity Diagram - Join Notation

 Activity Diagram - Object Notation

 Activity Diagram - Send Signal Notation

 Activity Diagram - Accept Event Notation

 Activity Diagram - Partition (Swimlane) Notation

 Activity Diagram - Frame Notation and Parameters

 UML Sequence Diagram and Notations

 UML State Machine Diagram and Notations

 UML Use Case Diagram and Notations

 MS Visio 2010 - UML Drawing Tool

 References

 PDF Printing Version