ZEIT2301Design of Information Systems

Functional Design:Activity Diagrams

School of Engineering and Information TechnologyUNSW@ADFA

Dr Kathryn Merrick

Topic 03: Activity Diagrams

Objectives Understand and use the notation for activity diagrams,

a form of functional modelling

References Text: Ch 5

Modelling business processes with Activity Diagrams and Use cases

Activity Diagrams and Use Cases are useful tools for modelling business functions

Activity diagrams model the behaviour in a business process Illustrate the business activities that are performed and how

objects (data) move amongst them.

Use Cases model the interaction of the system with its environment

Modelling business processes with Activity Diagrams

Activity diagrams can be used at different levels of abstraction to model

High-level business workflows that involve several Use cases The details of an individual Use case Specific details of an individual object method

eg how postage charges should be calculated for a product ordered online.

Need to consider: destination (domestic, international), weight, dimensions, fragility, etc

Modelling business processes with Activity Diagrams

Activity diagrams are similar to traditional flow charts

But…

include notation for modelling concurrent (parallel) activities

and complex decision processes

Creating Activity Diagrams

Determine the context or scope of the activity being modelled and then give the diagram an appropriate title.

Identify the activities, control flows, and object flows (eg data, documents) that occur between the activities.

Identify any decisions that are part of the process being modelled.

Identify any prospects for parallelism in the process.

Activity Diagram: Notation

Activity Diagram: Notation

Sample Activity Diagram

Sample Activity Diagram with Swimlanes

Business Process Modelling

Business process models describe the activities that collectively support a business process

A very powerful tool for communicating the analyst’s current understanding of the requirements with the user

Business Process Modelling

Example from BPMI.org

Summary

After today’s lecture you should be able to Draw activity diagrams for simple business scenarios.