An Approach for Creating Sentence Patterns for Quality Requirements

I held this talk at the 2016 IEEE International Requirements Engineering Conference in Beijing, China

Transcript

1. An Approach for Creating Sentence Patterns for Quality Requirements RePa 2016, Beijing, China September 13, 2016 Jonas Eckhardt1, Andreas Vogelsang2, Henning Femmer1 1 Technische Universität München 2 Technische Universität Berlin @andivogelsang
2. Sentence Patterns / Requirements Templates Sentence patterns provide a way to embody comprehensive and structured knowledge about requirements concerning a specific quality attribute [1] But: • Sentence patterns mostly for functional requirements • Relevant information depends on the context (how reqs are used) 2 Example: „The response time of the system shall be less than 1s.“ [1] S. Withall. Software Requirement Patterns. Microsoft Press, 2007
3. Quality Requirements But: • Definitions of quality attributes are not very precise • No support for specifying quality requirements 3 [ISO 25010] Performance – Time behavior: The degree to which the response and processing times and throughput rates of a product or system, when performing its functions, meet requirements.
4. Our Contribution An approach for creating sentence patterns for quality requirements that 1. provides a precise and explicit definition of the relevant information for a quality attribute 2. allows customization for a specific (usage) context 4
5. 1. Extraction of Content Elements 5 Search literature for definitions of quality attribute Extract content elements and arrange them in a content model Performance – Time behavior: The degree to which the response and processing times and throughput rates of a product or system, when performing its functions, meet requirements. System Response time Processing time Throughput rate Function has has has performs
6. 2. Definition of Content Elements 6 Provide a definition for each content element informal Content element Definition Throughput rate The number of answered requests per time interval … … formal [2] [2] based on: M. Broy. A logical basis for component-oriented software and systems engineering. The Computer Journal, 53(10), 2010
7. 3. Context-dependent Customization Associate development activities with relevant content elements 7 Create Test Case Implement Requirement Measurement Period Prioritize Requirement Plan Test Execution mandatory optional Measurement Location Modality
8. 4. Concretization 8 Translate content model parts to sentence fragments … … … Observation Frame “between event [A] and event [B]” Event start end
9. Sentence Patterns for Performance Requirements 9 a) Time Behavior Requirements b) Throughput Requirements c) Capacity Requirements d) Auxiliary Conditions
10. Overview of Our Approach 10
11. So What? • Syntactic analysis of requirements – A quality requirement is strongly complete if all mandatory content elements are explicitly contained in its textual representation. – A quality requirement is weakly complete if all mandatory content elements are explicitly or implicitly contained in its textual representation. – A quality requirement is incomplete if at least one mandatory content element is missing in its textual representation. • Analysis of the content of requirements in practice 11 Spoiler! (50 performance requirements from practice): • 68% incomplete • 32% complete (18% strongly complete) Spoiler! (50 performance requirements from practice): • 34% of reqs only consider a specific function • Only 2% of reqs mention a specific platform
12. Summary Thank you. @andivogelsang andreas.vogelsang@tu-berlin.de Existing sentence patterns for QR are too general and lack customization Our Approach The cool stuff: Check reqs for completeness Analysis of used content elements Presentation on performance reqs in practice! Wednesday, 10:30 AM, Meeting Room No.1
13. Backup 13