LAB OF SOFTWARE ARCHITECTURES
AND INFORMATION SYSTEMS
FACULTY OF INFORMATICS
MASARYK UNIVERSITY, BRNO
ROADMAP TO SOFTWARE QUALITY
Barbora Bühnová
buhnova@fi.muni.cz
PV260 COURSE INTRODUCTION
Outlineofthelecture
• Course introduction
• Course motivation and goals
• Course organization
• Our team
• Roadmap to quality assurance methods
• Define quality issues
• Prevent quality issues
• Detect quality issues
• Repair quality issues
• Keep track of quality issues
• Choose well, plan well
© B. Bühnová, PV260 Software Quality
Outlineofthelecture
• Course introduction
• Course motivation and goals
• Course organization
• Our team
• Roadmap to quality assurance methods
• Define quality issues
• Prevent quality issues
• Detect quality issues
• Repair quality issues
• Keep track of quality issues
• Choose well, plan well
© B. Bühnová, PV260 Software Quality
Coursemotivationandgoals
“People forget how fast you did a job – but they remember
how well you did it” – some guy named Howard Newton
• The aim of the course is to help the students to
• understand activities contributing to building high-quality software;
• develop critical thinking and be able to identify code flaws related to
reliability, performance, scalability, maintainability and testability;
• be able to refactor existing code to improve different quality attributes;
• have practical experience with software testing and related tools.
© B. Bühnová, PV260 Software Quality
Outlineoflectures
Lect 1. Course organization. Roadmap to software quality engineering methods.
Lect 2. Requirements and test cases. From unit testing to integration testing.
Lect 3. Quality and testing in agile. Practical insights on QA in real product
development.
Lect 4. Clean Code & SOLID principles. Bad code smells and code refactoring.
Lect 5. Performance engineering and performance testing.
Lect 6. Automated testing and testability.Continuous integration.
Lect 7. Software measurement and metrics, and their role in quality improvement.
Lect 8.The role of software architecture.
Lect 9. Focus on quality attributes and conflicts between them.
Lect 10. Static code analysis and code reviews.
Lect 11. Challenges of quality management in cloud applications.
Lect 12. Software quality management process. Course summary.
Colloquium event
© B. Bühnová, PV260 Software Quality
Courseorganization
• Lectures
• Shared by us and experts from companies
• May not be recorded
• Final colloquium event after the end of semester
• Seminars
• Practical assignments on computers
• Teamwork, homework, projects
• 2 Java groups – taught by LaSArIS lab members
• 1 C# group – taught by YSoft experts
© B. Bühnová, PV260 Software Quality
Courseorganization
• Evaluation
• 45 points for seminar assignments
• 10 seminar activity points
• 10 lecture activity points
• 35 points for final colloquium assessment, consisting of
• obligatory attendance at the final colloquium event and
• final written test
• Minimum of 70 points for passing the course
• Colloquium event
• On June 4, between 9-14h
• Discussion groups led by industrial experts
• Student presentations of outcomes
• Written test (at the end of the day, or on a separate term)
© B. Bühnová, PV260 Software Quality
Our team
© B. Bühnová, PV260 Software Quality
• Ondřej Krajíček
• Martin Osovský
• Radim Göth
• and others
• Barbora Bühnová
• Bruno Rossi
• David Gešvindr
• Stanislav Chren
• Jaromír Skřivan
• Lukáš Pitoňák
• Jakub Papcun
• Jan Svoboda
• JanVerner• Jiří Pokorný
• Pavel Macík
• MartinVečeřa
Outlineofthelecture
• Course introduction
• Course motivation and goals
• Course organization
• Our team
• Roadmap to quality assurance methods
• Define quality issues
• Prevent quality issues
• Detect quality issues
• Repair quality issues
• Keep track of quality issues
• Choose well, plan well
© B. Bühnová, PV260 Software Quality
QualityAssurance(QA)methods
© B. Bühnová, PV260 Software Quality
Usability testing
Security testing
Security tactics
RoadmaptoQA methods
Prevent
quality issues
Detect
quality issues
Repair
quality issues
Keep track of
quality issues
Define
quality issues
© B. Bühnová, PV260 Software Quality
Definequalityissues
• Software quality is commonly
defined as the capability of
a software product to conform
to requirements [ISO/IEC 9001].
• Requirements engineering
• Software metrics
• ’You cannot manage what you cannot measure’
• Quality attributes
• Of a product, process and resources
© B. Bühnová, PV260 Software Quality
Prevent
quality issues
Detect
quality issues
Repair
quality issues
Keep track of
quality issues
Define
quality issues
customer needs
What"quality"meanstoyou?
…andyourcustomer?
…andyourmanager?
© B. Bühnová, PV260 Software Quality
TheSoftwareQuality Iceberg
EXTERNAL QUALITY
INTERNALQUALITY
Visible / Symptoms
Invisible / Root
usability
accuracy
cost
performance
reliability
program structure
complexity
coding practices
testability
reusability
maintainability
flexibility
understandability
security
testinginspection
Inspiration from [5]
manualorautomated?
measurableornot?
© B. Bühnová, PV260 Software Quality
Thebig five
• Along the course we will focus on:
• Maintainability – ease of change (without increased technical debt)
• Performance – response time and efficiency in resource utilization
• Reliability – probability of failure-free operation over a period of time
• Testability – degree to which the system facilitates testing
• Scalability – system’s ability to handle growing work load
• Quality attributes studied in related courses:
• Security – system’s ability to protect itself from attacks
• Usability – ease of system use and learnability
© B. Bühnová, PV260 Software Quality
Preventqualityissues
• Coding best practices
• Clean code, SOLID principles
• Design patterns
• Pair programming
• Code conventions
• Language specif. recommendations
• Quality assurance processes
• V-model of testing
• Standards for development process improvement
• CMMI and ITIL reference models
• ISO 9000, ISO/IEC 25010
© B. Bühnová, PV260 Software Quality
Prevent
quality issues
Detect
quality issues
Repair
quality issues
Keep track of
quality issues
Define
quality issues
Detectqualityissues
• Testing functional requirements
• Manual or automated
• Testing non-functional req.
• Performance, usability, security
testing
• Design inspections
• Manual inspections of design artifacts
• Code reviews
• Manual inspections of code
• Automated static code analysis
© B. Bühnová, PV260 Software Quality
Prevent
quality issues
Detect
quality issues
Repair
quality issues
Keep track of
quality issues
Define
quality issues
Roadmaptosoftwaretesting
© B. Bühnová, PV260 Software Quality
Inspired from [1]
Test cases
Test resources
Test plan
Testing
Strategy
Unit
Component
Functional
Test
Backend
Middleware
Third party
System and
IntegrationTest
Functional
Non-functional
Regression
ReleaseTest
Usability
Learnability
Requirements
Acceptance
(User)Test
Application
Infrastructure
Post-production
Tuning
Requirements
Acceptance
Criteria
Test management
Functional testing
Non-functional testing
Tuning
Specify Design Prototype Configure Validate Deploy Maintain
DevelopmentTestingEnd-to-EndView
ImplementationCycle
Penetration
Red team
SecurityTest
Response time
Stress
PerformanceTest
Repairquality issues
• Functional issue
• Code repair
• Reliability issue
• Fault tolerance mechanisms
• Performance issue
• Concurrency, effective resource utilization,
identify and remove system bottlenecks
• Security issue
• Identify and remove system vulnerabilities (single points of failure)
• Maintainability issue
• Refactoring to clean code principles, to design patterns
© B. Bühnová, PV260 Software Quality
Prevent
quality issues
Detect
quality issues
Repair
quality issues
Keep track of
quality issues
Define
quality issues
Keeptrackofqualityissues
• Issue tracking
• Supports the management of
issues reported by customers
• Technical debt management
• Level of code quality degradation
• Work that needs to be done before
a particular job can be considered complete or proper
• Configuration management
• Version management and release management
• System integration
© B. Bühnová, PV260 Software Quality
Prevent
quality issues
Detect
quality issues
Repair
quality issues
Keep track of
quality issues
Define
quality issues
RoadmaptoQAmethods–theBigPicture
Prevent quality issues
- Coding best practices
- Code conventions
- QA processes
- Standards
Detect quality issues
(Non)Functional testing Design
inspections Code
reviews Static
code analysis Repair
quality issues
- Reliability tactics
- Performance tactics
- Security tactics
- Maintainability tactics
Keep track
of quality issues
Issue tracking Technical
debt management Configuration
management Define
quality issues
- Requirements engineering
- Quality attributes
© B. Bühnová, PV260 Software Quality
Outlineofthelecture
• Course introduction
• Course motivation and goals
• Course organization
• Our team
• Roadmap to quality assurance methods
• Define quality issues
• Prevent quality issues
• Detect quality issues
• Repair quality issues
• Keep track of quality issues
• Choose well, plan well
© B. Bühnová, PV260 Software Quality
Choosewell,plan well
• Think well about your requirements
and the cost of the quality
© B. Bühnová, PV260 Software Quality
Choosewell–Combinationisthekey
© B. Bühnová, PV260 Software Quality
From [2,3], see also RebelLabs reports [4]
Plan well –The PowerofAnalogy
• Airplane Servicing
• Requires regular servicing e.g. every 100,000 miles.
• Takes place even if everything seems to work all right,
because we cannot afford a failure.
• Technical Debt Management
• Introduced by WardCunningham
• Analogy of quality degradation with financial debt
– if not paid off, interests increase.One can get into trouble.
• Sometimes it is wise to “borrow money”
• When one expects to have more money in the future (start-up company)
• When one needs to act fast not to miss a market opportunity
• When one expects money devaluation (e.g. developers will become
more experienced, it will be easier to understand user needs)
© B. Bühnová, PV260 Software Quality
Can we quantify it?
Takeaways
• Quality assurance (QA) is much more than testing, including
many different methods to
• prevent, detect, repair and keep track of quality issues
• Combination of the methods is the key to successfulQA
• But choose well and plan well, not all methods are best for your project!
• Make sure you understand the needs of your customer
• Balance both internal and external quality attributes for both
the present and the future
Barbora Bühnová, FI MU Brno
buhnova@fi.muni.cz
www.fi.muni.cz/~buhnova
contact me
thanks for listening
© B. Bühnová, PV260 Software Quality
References
• [1]TestingYou PerformWhenYou Develop a SiebelApplication.Available online at
http://docs.oracle.com/cd/E14004_01/books/DevDep/Overview5.html
• [2] Steve McConnell. Code Complete:A Practical Handbook of Software
Construction, Second Edition. Microsoft Press, June 2004.
• [3] Kevin Burke. Why code review beats testing: evidence from decades of
programming research. Available online athttps://kev.inburke.com/kevin/the-best-
ways-to-find-bugs-in-your-code/
• [4] RebelLabs. 2013 Developer Productivity Report. Available online at
http://zeroturnaround.com/rebellabs/developer-productivity-report-2013-how-
engineering-tools-practices-impact-software-quality-delivery/
• [5] Jonathan Bloom.Titanic Dilemma:The SeenVersus the Unseen. Available online
at http://blog.castsoftware.com/titanic-dilemma-the-seen-versus-the-unseen/
© B. Bühnová, PV260 Software Quality