The Software Process. Software Process Activities. Functional Specification

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1 The Software Process Step and procedures executed by a software organization during the development of software Not a linear sequence of steps Many activities occur simultaneously or in random order Organizations often continually improve and change their software processes Software Process Activities Requirements Analysis and Definition System Design Prototyping Implementation and Coding Unit Testing Integration Testing System Testing (Alpha) Acceptance Testing (Beta) Help and Manual Generation Release Maintenance Functional Specification Formal document generated after a requirements analysis. Contains a detailed list of the functionality required for the system being built. Is a contract between the client and developers which states what functionality the end system will have. Only technical with respect to domain knowledge associated with the software product s purpose. 1

2 Sample Requirements Delivery Schedule Performance Deployment Configurability/Adaptability Portability Reliability Usability (User Interface Features) User Interface Standards System Functions Maintainability Coding Standards Functional Specification There should be no coupling between the functional specification and the design specification. The functional spec should be concerned with describing the functionality. Functional specification should decouple details of how the system is to be implemented. In the functional specification phase the customer should not think in design terms. Design Specification Formal document which describes how the features described in the functional specification document are to be implemented. Design Phases High level architectural design Detailed Design (Decomposition) object or module based Interleaved Design testing 2

3 Computer Aided Software Engineering (CASE) Tools (File) Version Management Tools Aka Source Code Control Supports multiple developers working on same code base Supports ability to track a module through it s development Supports software releases by tagging file versions Most tools store differences between file versions. Web interfaces Version Management Tools Rational ClearCase PVCS Version Manager Microsoft Visual SourceSafe CVS - Concurrent Versions System See this link: M/CMTools.html Software Engineering Tools Feature Tracking Tools Track System Requirements Track System Change Requests (Critical Incidents, aka bugs ) Can associate issue with source files, classes (integration with version management tools.) Responsibility for software requirements can be assigned to specific team members Priority of issues can be assigned and tracked 3

4 Feature Tracking Tools Any database Intersolv: PVCS Tracker Rational: ClearQuest Elsinore: Visual Intercept Integrates with Microsoft SourceSafe Specification/Design Tools Allow for system modeling and design Support diagramming in a standard notation such as UML Support code generation from models Specification/Design Tools supporting UML! " #%$'& ()+*+,-.(+/0 123,451& #76 *8 8 )9: :<;';';= (?>@+(5-<1>2<;=-3A+BC:3D FE G HIJK3 LMN! " #7O A>+1+/ 1& #76 *8 8 )9: :<;';';= -.(2<1;G,2<1= -<ABC:<D FE K J P J! " #%Q'R.S 1-38 T1(BPU $G& A+V5>+WNA& X?23UT1+& & (+, 5 #76 *8 8 )9: :<;';';= -.(Y15+512<AZ 8 = -<ABC:<D [H \ P N N! " #7](2<Y]+^M](2<YQG_`<]aT #76 *8 8 )9: :<;';';= 1238, = -<ABC:<D F! EcbedfE LJgh+< i! " #7j1(>+2<8 (+& 8 Ua(8 (/ Y23, 2 #76 *8 8 )9: :<;';';=,-<A5-<ABI)= -<ABG:3D 4

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6 Popular Design Tools Support UML notation Rational Rose Microsoft Visual Modeler Microsoft Visio UML Overview A standard notation for Views Diagrams Model elements» General mechanisms Views Used to describe a system A single graph can t describe all the different aspects. Functional Structure, interaction between components Nonfunctional Performance, reliability, deployment Organizational Work organization 6

7 Views Use-case view System as perceived by the end users Logical view Structural description Component view Division of work, dependencies between code modules Concurrency view For describing synchronization and communication aspects of a system Deployment view Describing how a system is deployable Use-Case Diagram Class Diagram Object Diagram State Diagram Sequence Diagram Collaboration Diagram Activity Diagram Component Diagram Deployment Diagram Diagrams Other Software Tools Automated testing tools Segue Quality Works Make/Build tools Metrics tools 7

8 A Basic Software Process System Design and Prototyping Implementation Requirements Analysis and Definition System Testing Software Process Models Waterfall Model Rapid Prototyping Model Spiral Model Build and Fix Model Incremental Model Waterfall Model Requirements Gathering Functional Specification Design Specification Implementation (coding) Unit/Integration Testing System and Acceptance Testing Delivery and Maintenance 8

9 Rapid Prototyping Model Develop Prototype Functional Specification Design Specification Implementation (coding) Often involves extending the prototype instead of recoding Unit/Integration Testing System and Acceptance Testing Delivery and Maintenance Spiral Model Incremental Model Requirements Gathering Functional Specification Design Implementation Unit/Integration Testing System Acceptance Testing Software Release 9

10 Software Processes and your Career As good Software Engineers you should strive to: Seek employment at organizations with higher process maturity Gaining experience at such organizations can help you understand how to build a quality process Seek to improve the maturity of the software process employed by your organization Software Processes and your Career Organizations with poor Software Processes will fail to deliver quality software on time. Example: Internet Startups Just because these companies are working in internet time, doesn t mean that they can ignore the rules of software development. If startups fail to have a mature software process they will fail. Capability Maturity Model (CMM) Software Engineering Institute (SEI), Carnegie-Mellon University Method for categorizing the maturity and quality of a software process used by software development organizations 10

11 Capability Maturity Model (CMM) Level 1: Initial Level Ad hoc process Level 2: Repeatable Level There is an informal process Code Versioning Feature Tracking Level 3: Defined Level Process is clearly defined, and documented. Efforts made to improve process Specification and Design Tools Used Capability Maturity Model (CMM) Level 4: Managed Level Process is clearly defined and documented and measured. Metrics used Dr. Henry s expertise Productivity and Quality Goals set, and adhered to. Level 5: Optimizing Level Process is defined, measured and optimized after each project iteration What CMM Levels have you experienced? 11