Follow Us
Categories
Archives
- December 2022
- November 2022
- October 2022
- February 2022
- October 2021
- September 2021
- August 2021
- July 2021
- June 2021
- May 2021
- January 2021
- November 2020
- October 2020
- August 2020
- April 2020
- February 2020
- January 2020
- October 2019
- September 2019
- July 2019
- May 2019
- April 2019
- March 2019
- February 2019
- January 2019
- December 2018
- October 2018
- September 2018
- August 2018
- July 2018
- April 2018
- February 2018
- January 2018
- December 2017
- November 2017
- October 2017
- September 2017
- August 2017
- July 2017
- June 2017
- May 2017
- April 2017
- March 2017
- February 2017
- January 2017
- December 2016
- November 2016
- October 2016
- September 2016
- August 2016
- July 2016
- April 2016
- January 2016
- December 2015
- November 2015
- October 2015
- September 2015
- August 2015
- July 2015
- June 2015
- May 2015
- January 2015
- December 2014
- November 2014
- October 2014
- September 2014
- August 2014
- July 2014
- June 2014
- May 2014
- April 2014
- March 2014
- February 2014
- January 2014
- November 2013
- September 2013
- August 2013
- July 2013
- June 2013
- May 2013
- April 2013
- February 2013
- January 2013
- November 2012
- October 2012
- August 2012
- July 2012
- June 2012
- May 2012
- April 2012
- March 2012
- December 2011
- November 2011
- June 2011
- May 2011
- April 2011
- March 2011
- February 2011
- January 2011
- December 2010
- November 2010
- October 2010
- September 2010
- August 2010
- July 2010
- June 2010
- May 2010
- April 2010
- March 2010
- February 2010
- January 2010
- December 2009
- November 2009
- October 2009
- September 2009
Tag Archives: Baker’s Dozen
The Baker’s Dozen of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
Use cases have become a core part of the requirements analyst’s arsenal. Used well they can bring dramatic increases in customer satisfaction and a whole host of other subtle benefits to software development.
The use case itself is very simple in concept: describe the functionality of the system in terms of interactions between the system and its external interactors. The focus of the use case is system usage, from an external perspective.
Despite this apparent simplicity, requirements analysts frequently struggle to write […]
The Baker’s Dozen of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
Rule 13: Say it with more than words
Use case descriptions are most commonly written in text format (albeit often a stylised, semi-formal style of writing). Text is a very effective method of describing the transactional behaviour of use cases – it’s readily understandable without special training; most engineers can produce it (although the ability to write basic prose does seem beyond the capability of many!); and it is flexible enough to deal with complex behaviours – for example, variable numbers […]
Posted in Design Issues
Tagged Analysis, Baker's Dozen, Notation, Requirements, UML, Use Cases
1 Comment
The Baker’s Dozen of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
Rule 12: Avoid variations on a theme
A common affliction amongst novice use case modellers (particularly those from a development background) is the desire to fettle the use case model – to organise it, revise it, balance it; and generally make it look more like a design model. Unfortunately, beyond a certain point this effort actually starts to degrade the utility and effectiveness of the model. More and more effort is put into a model that becomes less and less useful […]
Posted in Design Issues
Tagged actor, Analysis, Analysis Paralysis, Baker's Dozen, inheritance, Rule, Specialisation, UML, Use Cases
1 Comment
The Baker’s Dozen of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
Rule 9 – Build yourself a Data Dictionary
Transactions between the actors and the system typically involve the transfer of data. This data has to be defined somewhere. If you’ve built a Domain Model ( see Part 5 – here) most of the data will be identified there; but even then the class diagram is not always the most practical place to capture the sort of information you need to record.
Another way to capture this information […]
Posted in Design Issues
Tagged Analysis, Baker's Dozen, Data Dictionary, Requirements, UML, Use Case
Leave a comment
The Baker’s Dozen of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
RULE 7: Describe ALL the transactions
A use case, as the name implies, describes the usage of the system from the point of view of some beneficiary (our Actor). It is NOT (as I seem to spend my whole life telling people) is just the system function, organised as some sort of graphical ‘sub-routine’. This means the use case description must include the expected behaviour of the actors as well as the expected behaviour of the system.
This can […]
Posted in Design Issues
Tagged Analysis, Baker's Dozen, Requirements, Transaction, UML, Use Cases
Leave a comment
The Baker’s Dozen of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
RULE 5: Focus on goals, not behaviour
There is a subtle distinction between the functional behaviour of the system and the goals of the actors. This can cause confusion: after all, the functional behaviour of the system must surely be the goal of the actor?
It is very common, then, for engineers to write use cases that define, and then describe, all the functions of the system. It is very tempting to simply re-organise the software requirements into functional areas, each […]
Posted in Design Issues, UML
Tagged Analysis, Baker's Dozen, Design Case, Goals, Requirements, Use Case
1 Comment
The Baker’s Dozen of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
RULE 3: Never mix your Actors
The UML definition of an Actor is an external entity that interacts with the system under development. In other words: it’s a stakeholder.
Having analysed all your stakeholders (see Part 3 ) it’s tempting to stick them (no pun intended) as actors on a use case diagram and start defining use cases for each.
Each set of stakeholders (Users, Beneficiaries or Constrainers) has its own set of concerns, language and concepts:
Concerns.
Each stakeholder group has a different […]
Posted in Design Issues, UML
Tagged Analysis, Baker's Dozen, Requirements, UML, Use Cases
Leave a comment
The Baker’s Dozen of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
RULE 2: Understand your stakeholders
A Stakeholder is a person, or group of people, with a vested interest in your system. Vested means they want something out of it – a return on their investment. That may be money; it may be an easier life.
One of the keys to requirements analysis is understanding your stakeholders – who they are, what they are responsible for, why they want to use your system and how it will benefit them.
It’s important to […]
Posted in Design Issues, UML
Tagged Analysis, Baker's Dozen, Requirements, Stakeholder, UML, Use Cases
1 Comment
The Baker’s Dozen Of Use Cases
Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
He specialises in C++, UML, software modelling, Systems Engineering and process development.
Latest posts by Glennan Carnie (see all)
- Practice makes perfect, part 3 – Idiomatic kata - February 27, 2020
- Practice makes perfect, part 2– foundation kata - February 13, 2020
- Practice makes perfect, part 1 – Code kata - January 30, 2020
RULE 1: Use Cases Aren’t Silver Bullets
There are a couple of popular misconceptions around use cases:
Misconception 1: The use cases are the requirements of the system
Contrary to what many engineers believe (and many authors have written) the complete set of use cases do NOT constitute its full set of requirements for the system.
A use case model is an analysis tool. They are a mechanism for organising the functional behaviour of the system and reflecting it back to the […]