©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 1 Tools of Software Development l 2 types of tools used by software engineers: 1.Analytical tools –Stepwise refinement –Cost-benefit analysis –Software metrics 2.CASE tools

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 2 CASE (Computer-Aided Software Engineering) Tools l Software that is used to support software process activities l Provides software process support by automating some process activities providing information about the software being developed l Currently used in every phase/workflow of life cycle

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 3 CASE Tools l Benefits Improve software quality Enforce discipline Help communication between development team members Information is illustrated through diagrams that are typically easier to understand Development information is centralized

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 4 CASE Tools l Benefits Reduction of time and effort Tasks are much faster to complete and alter Enhance reuse of models or models’ components Can reduce maintenance costs

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 5 CASE Tools l Problems Limitations in flexibility of documentation Major danger: completeness and syntactic correctness does NOT mean compliance with requirements Costs associated with the use of the tool Purchase price Training

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 6 3 Categories of CASE Tools l Tools l Workbenches l Environments

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 7 3 Categories of CASE Tools l Tools Support individual process tasks Examples: Checking the consistency of a design Compiling a program Comparing test results

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 8 CASE Tools l Upper-CASE tools (front-end tools) Assist developer during requirements, analysis, and design workflows or activities l Lower-CASE tools (back-end tools) Assist with implementation, testing, and maintenance workflows or activities l Integrated CASE tools (I-CASE) provide support for the full life cycle REVIEW THE UNIFIED PROCESS to SEE WHERE EACH OF THESE TOOLS ARE USED

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 9 3 Categories of CASE Tools l Workbenches Collection of tools that together support: Process workflows (requirements, design, etc.) One or two activities where an activity is a related collection of tasks Commercial examples: PowerBuilder Software Through Pictures Software Architect

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 10 3 Categories of CASE Tools l Environments Support the complete software process or, at least, a large portion of the software process Normally include several different workbenches which are integrated in some way

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 11 Taxonomy of CASE Tools

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 12 Components of CASE CASE repository Document Generator Design Generator Analysis tool Code Generator Drawing Tool Error-checking tool Security and Version Control Screen and Report Generator Prototyping Tool Database Generator

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 13 Components of CASE l CASE repository Central component of any CASE tool Also known as the information repository or data dictionary

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 14 Components of CASE l CASE repository Centralized database Allows easy sharing of information between tools and SDLC activities Used to store graphical diagrams and prototype forms and reports during analysis and design workflows Provides wealth of information to project manager and allows control over project Facilitates reusability

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 15 Components of CASE l CASE repository acts as: Information repository Combines information about organization’s business information and application portfolio Provides automated tools to manage and control access Data dictionary Used to manage and control access to information repository Facilities for recording, storing and processing resources Useful for cross-referencing

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 16 Components of CASE l Diagramming tools Allow you to represent a system and its components visually Allows higher level processes to be easily decomposed Can examine processes or data models at high or low level

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 17 Components of CASE l Screen and report generators Used to Create, modify and test prototypes of computer displays and reports Identify which data items to display or collect for each screen or report Some tools have templates

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 18 Components of CASE l Analysis tools Generate reports that help identify possible inconsistencies, redundancies and omissions Generally focus on diagram completeness and consistency data structures and usage

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 19 Components of CASE l CASE documentation generator tools Create standard reports based on contents of repository Need textual descriptions of needs, solutions, trade- offs, diagrams of data and processes, prototype forms and reports, program specifications and user documentation High-quality documentation leads to 80% reduction in system maintenance effort in comparison to average quality documentation

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 20 CASE workbenches l A coherent set of tools that is designed to support related software process activities such as analysis, design or testing. l Analysis and design workbenches support system modelling during both requirements engineering and system design. l These workbenches may support a specific design method or may provide support for a creating several different types of system model.

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 21 An analysis and design workbench

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 22 Analysis workbench components l Diagram editors l Model analysis and checking tools l Repository and associated query language l Data dictionary l Report definition and generation tools l Forms definition tools l Import/export translators l Code generation tools

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 23 Computer-aided software engineering l Computer-aided software engineering (CASE) is software to support software development and evolution processes. l Activity automation Graphical editors for system model development; Data dictionary to manage design entities; Graphical UI builder for user interface construction; Debuggers to support program fault finding; Automated translators to generate new versions of a program.

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 24 Case technology l Case technology has led to significant improvements in the software process. However, these are not the order of magnitude improvements that were once predicted Software engineering requires creative thought - this is not readily automated; Software engineering is a team activity and, for large projects, much time is spent in team interactions. CASE technology does not really support these.

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 25 CASE classification l Classification helps us understand the different types of CASE tools and their support for process activities. l Functional perspective Tools are classified according to their specific function. l Process perspective Tools are classified according to process activities that are supported. l Integration perspective Tools are classified according to their organisation into integrated units.

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 26 Functional tool classification

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 27 Activity-based tool classification

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 28 CASE integration l Tools Support individual process tasks such as design consistency checking, text editing, etc. l Workbenches Support a process phase such as specification or design, Normally include a number of integrated tools. l Environments Support all or a substantial part of an entire software process. Normally include several integrated workbenches.

©Ian Sommerville 2004Software Engineering, 7th edition. Chapter 8 Slide 29 Tools, workbenches, environments