Chapter 20

The Software-Quality Landscape

Characteristics of Software Quality Techniques for Improving Software

Quality Relative Effectiveness of Quality

Techniques When to Do Quality Assurance The General Principle of Software

Quality

Correctness Usability Efficiency Reliability Integrity Adaptability Accuracy Robustness

Maintainability Flexibility Portability Reusability Readability Testability Understandability

Set quality objectives Explicitly value quality-assurance

activity Develop test strategy Apply software engineering guidelines Have informal technical review before

formal one Follow formal review process Have external audit

Processes that are not explicitly quality assurance activities also affect quality Change control procedure Measurement of results prototyping

Percent of defects detected defects found / total defects %

Cost of finding defects

Cost of fixing defects

Early in the stage

Through out the projects

Improve quality reduces development cost Dirty, quick code may seems cheap at the

beginning but cost heavily as the project goes.