Three- Reflective Journal

8/6/2020 Laureate International Universities

https://laureate-au.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_89880_1&content_id=_8975601_1&mode=reset 1/7

MODULE 3.1MODULE 3.1

Use cases, user stories and business rules

Introduction:

Use cases and user stories are the two most commonly used approach to

analyse, model and communicate requirements. In Module 3.1, you will

learn the various elements in a use case and use case diagram. You will also

learn the pattern of a user story.

Use case

A use case describes a sequence of interactions between the System to be

built and an actor that results in the actor being able to achieve some goals

with the System. There are three basic elements to a use case: an actor, a

use case title, and a usage scenario.

8/6/2020 Laureate International Universities

https://laureate-au.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_89880_1&content_id=_8975601_1&mode=reset 2/7

An actor is a “participant” who interacts with the system to perform a use

case. Note that the participant does not necessarily to be a person, it can

sometimes be another software or even hardware. The tile of a use case is

written in the form of a verb followed by an object. For example, view

assignments, download assignment. A usage scenario describes the steps

whereby the actor performs a use case. Essential Resources 1 Video 1-4 and

Essential Resources 2 and 3 (Chapter 8) discusses in great depth on use

case, use case diagram and speci�cation.

User story

User stories are commonly used in Agile methodology. A user story is

expressed in according to the following pattern:

As a <type of user>, I want <some goal> so that <some reason>.

For example, as a Lecturer, I want to download students’ assignment so that

I can mark them o�ine. Essential Resource 1 Video 5 talks brie�y about user

stories.

Business rules

Almost all organisations operate according to an extensive set of policies,

procedures, legislations, and industry standard. For example, Torrens

conducts its academic operations pursuant to various of academic Policy

and Procedure, e.g. Assessment Policy and Procedure, Review of Grade

Policy and Procedure just to name a few. Business rules can be classi�ed

according to di�erent taxonomies. In Essential Resources 3 (Chapter 9), you

will learn the various types of business rules and how they �t into user

requirements and functional requirements.

Essential Resources:

View �ve introductory videos on use cases and user stories

8/6/2020 Laureate International Universities

https://laureate-au.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_89880_1&content_id=_8975601_1&mode=reset 3/7

Video 1 Use cases (4m 57s): https://www.lynda.com/Python- tutorials/Use-cases/731735/5002896-4.html? org=think.edu.au

Video 2 Identifying the actors (3m 39s): https://www.lynda.com/Python-tutorials/Identifying- actors/731735/5002897-4.html?org=think.edu.au

Video 3 Identifying the scenarios (4m 18s): https://www.lynda.com/Python-tutorials/Identifying- scenarios/731735/5002898-4.html?org=think.edu.au

Video 4 Diagramming use cases (3m 53s): https://www.lynda.com/Python-tutorials/Diagramming-use- cases/731735/5002899-4.html?org=think.edu.au

Video 5 User stories (3m 53s): https://www.lynda.com/Python-tutorials/User- stories/731735/5002900-4.html?org=think.edu.au

Video 1 discusses some basic element of a use case, viz. the title of a

case use, actor or actors, success scenario; it also brie�y mentioned a

few additional details of a use case.

Video 2 focuses on identifying the actors. By the end of this video, you

should be able to answer the following questions:

Why they are called actors rather than uses?

Do all the actors of a system have to be humans?

Who are primary actors and secondary actors?

Is there a hierarchy of actors?

Video 3 talks about scenarios. By the end of this video, make sure you

understand:

How detail the scenarios should be?

What is a successful scenario?

Video 4 in less than 4 minutes talks very brie�y about use case

diagrams. View this video and make sure you understand:

How to represent a use case?

How to draw an actor?

8/6/2020 Laureate International Universities

https://laureate-au.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_89880_1&content_id=_8975601_1&mode=reset 4/7

How to de�ne the boundary of a system?

How to indicate that an actor interacts with a use case? Are the links directional?

Video 5 talks about an alternative way to describe user application,

that is, user stories. You should learn the “As a…I want…so that…”

pattern to describe a user story. You also need to understand the

di�erences between user stories and use cases. Are they a

replacement of one another?

Kratochvíl, M., & McGibbon, B. (2003). UML xtra-light: How to

specify your software requirements. New York: Cambridge

University Press. (2003). Retrieved from:

https://lesa.on.worldcat.org/oclc/56416112

Read extract from UML xtra-light : how to specify your software

requirements.

Read Chapter 3 Adding Rigor to the Requirements, page 27 – 46. With

the foundation you built in Essential Resource 1, you will learn an

extra layer of complexity in use case and use case diagrams. When

you read this Chapter, make sure you understand the following

concept:

Generic actors

<<extend>> and <<include>> relationship between use cases;

Use-case generalisation;

The list of traps from page 39 to 45.

This short read should give you a working understanding of use case

diagram.

Wiegers, K., & Beatty, J. (2013). Software requirements (3rd

ed.). Redmond, WA: Microsoft Press.

8/6/2020 Laureate International Universities

https://laureate-au.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_89880_1&content_id=_8975601_1&mode=reset 5/7

Read Chapter 8 Understanding user requirements and Chapter 9

Playing by the rules. These two Chapters in Wiegers provide a

comprehensive discussion on use case, and business rules. It also

discusses relatively brie�y about user stories.

Once you have viewed and read the �rst two Essential Resources,

these two chapters should be an easy read. Make sure you focus on

and understand the following concepts:

Preconditions and postconditions (Chapter 8)

Normal �ows, alternative �ows, and exceptions (Chapter 8)

Use case and functional requirements (Chapter 8)

Types of business rules (Figure 9-1, Chapter 9) and their de�nitions and examples

Sources of business rules (Chapter 9)

Business rules and requirements (Chapter 9)

Learning Activity:

Collaborative learning activity

In the facilitated learning sessions, form a group of three

students, draw a use case diagram for Blackboard (the ‘System’). You

should:

Identify all actors. Besides the most obvious actors (e.g. students, learning facilitators), are there any other actors? Are there any actors that are not human? For each of the use case, who is the primary actor? Who are the secondary actors?

Identify all major use cases and the relationship between them.

Identify the boundary of the System.

For each student in the group, choose one use case and document the

speci�cation for that use case similar to Figure 8-3 in Wiegers. Make

sure you include the following elements:

8/6/2020 Laureate International Universities

https://laureate-au.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_89880_1&content_id=_8975601_1&mode=reset 6/7

ID and Name

Primary Actor

Secondary Actors

Description

Tigger

Precondition and postcondition (if any)

Normal �ow

Alternative �ows (if applicable)

Exceptions (if applicable)

Download and read the following documents from

https://www.torrens.edu.au/policies-and-forms:

Assessment Policy for Higher Education Coursework and ELICOS

Academic Integrity Policy

Academic Integrity Procedure

Can you identify from the three Policy and Procedures above any

business rules of the following kind?

Facts

Constraints;

Action Enablers;

Inferences;

Computations;

Finally, post your answers (a use case diagram, use case speci�cations,

and business rules) to the Module 3.1 discussion forum. Please read

through other students’ post and comment on the following aspects

of their answers:

whether the use case diagram complies with the use case diagram notation convention;

whether the use case diagram captures all major use cases;

8/6/2020 Laureate International Universities

https://laureate-au.blackboard.com/webapps/blackboard/content/listContent.jsp?course_id=_89880_1&content_id=_8975601_1&mode=reset 7/7

whether the actors in use case diagram are correct and complete; have they considered interactions with other Systems (i.e. other than Blackboard).

whether the use case speci�cation include all the key elements;

whether the business rules are correct and correctly categorised.

To participate in the Discussion Forum, click here to scroll to the

bottom of this page then click on the "Module 3 - Discussion

Forum" link.

Note: The Learning activities above are not part of summative/graded

assessment; however they are designed to prepare you for incremental

graded assessment and expand your learning.

These activities encourage a community learning experience between peers,

and provide opportunities for facilitators to o�er formative feedback,

throughout a module, to the student cohort.