11.1

Lecture 11

CASE tools

IMS2805 - Systems Design and Implementation

11.2

References

Prescribed text:

Avison, D.E. & Fitzgerald, G. (2003). Information Systems Development: Methodologies, Techniques and Tools. (3rd ed), McGraw-Hill, London.

Chapters 17, 18,

HOFFER, J.A., GEORGE, J.F. and VALACICH (2002) 3rd ed., Modern Systems Analysis and Design, Prentice-Hall, New Jersey, Chapter 4

11.3

Quality and productivity

“solutions” include:

user participation JAD (Joint Application Design) prototyping automated and other tools RAD (Rapid Application Development) reuse

11.4

What are CASE tools?

computer-aided software tools that provide automated support for some portion of the systems development process

provide an engineering-type discipline to improve productivity and increase the quality of information systems

CASE tools may run on various mini and mainframe systems, but the PC is the dominant CASE workstation

11.5

CASE tools

CASE (Computer Assisted Software Engineering) tools

Objective of CASE tool usage:

higher quality systems, a less expensive and more productive system development process

“automated and integrated software development tools, techniques and methodologies that add significant value by increasing the productivity of the application development process and the quality of the applications that they're used to develop”

Stone (1993) p.8

11.6

CASE tools

Objectives to improve the quality of the systems developed: e.g.

better and more complete specifications and designs to improve the productivity of systems development: less

people and faster to ease and improve consistency of specifications,

conformity of designs, and testing through automated checking

to improve the integration of development activities via the use of common methodologies and techniques

to improve the quality and completeness of documentation

11.7

CASE tools

Objectives

to improve the management and control of projects to promote consistency across projects within the

organisation to promote consistency and quality of systems across

the organisation to promote resuability to reduce maintenance effort

11.8

CASE tools

core CASE tool functionality: graphical facilities for diagrams and modelling data dictionary automated documentation

additional functionality: code generation from system specifications and models automatic audit trail of changes project management facilities enforced diagramming and documentation standards

11.9

diagramming tools screen and report generators analysis tools a central repository documentation generators code generators

Components of CASE Tools

11.10

diagramming toolsenable graphical representation of system data, processes, and control structures

screen and report generatorshelp to prototype how systems “look” and “feel” to users help to identify data and process requirements

analysis toolsautomatic checking for correctness, completeness, and consistency of specifications in diagrams, reports, forms

Components of CASE Tools

11.11

a central repositoryenables integrated storage of systems specifications and project management information

documentation generatorshelp to produce both technical and user documentation in standard formats

code generatorsautomatic generation of program and database definition code directly from the design documents, diagrams, reports and forms

Components of CASE Tools

11.12

the repository is central to the CASE tool for integration to allow sharing between tools and SDLC activities

a centralised database containing all form and report definitions, diagrams, data definitions (data flows, entities etc), process flows, functions, process logic, other organisational and system components

common terminology, notations, methods to support integration

potential benefits:

supports co-ordination of team members and effort

promotes reusability

CASE tools: the CASE repository

11.13

Upper CASE

designed to support the earlier lifecycle phases:

IS planning, project identification and planning, systems analysis, design

Lower CASE

designed to support the implementation and maintenance phases of systems development

I-CASE (integrated CASE)

“seamless” integration of products and tools across lifecycle phases via a common repository

(see Avison & Fitzgerald 2003, Chapter 18)

Types of CASE tools

11.14

Cross lifecycle CASECASE tools used to support activities that occur across multiple phases of the SDLC

e.g. project management:

developing estimates of time and resources, scheduling, monitoring project progress

production of documentation

the repository and document generators are used across multiple lifecycle phases

CASE tool usage

11.15

the adoption of CASE is closely related to the use of a formal, standardized systems development process or methodology:

many CASE tools force or encourage analysts to follow a specific methodology

organizations without a widely used methodology or an approach that is compatible with a CASE tool will have difficulties

CASE adoption has been slower than expected due to several factors including:

cost, training needs, front end lifecycle effort

Implementing CASE tools in organisations

11.16

startup costs

I-CASE costs per analyst: $5,000 to $50,000

only large-scale system builders can spend this

smaller organisations use tools with less functionality

training

for every dollar spent on tools, half to double that spent on training

front end lifecycle effort

the big benefits come in later lifecycle phases: construction, testing, implementation, maintenance

early phases lengthened by up to 40%

(see Hoffer et al 2002, chapter 4)

Implementing CASE tools in organisations

11.17

Why organisations resist CASE tools

common resisting organisational factors for CASE adoption:

high cost of purchasing high cost of training personnel low organisational confidence in the IT department to

deliver high quality systems on time and within budget lack of methodology and standards CASE seen as a threat to job security lack of confidence in CASE products

11.18

CASE tool implementation

critical success factors:

the right tools a CASE implementation strategy a systems development methodology the methodology must be structured to facilitate the

use of CASE tools a CASE-compatible culture appropriate human resources appropriate expectations

11.19

Selecting CASE tools

compatible with systems development methodology/approach

compatible with technology architecture development and application environment organisational culture implementation strategy vendor support

11.20

Systems development using CASE tools

changes in work practices: focus on analysis and design “automatic” documentation generation maintain designs modifications to analysis and design products project management project team structures task structures differences between CASE-based vs manual versions of

SDMs

11.21

Evolution and future of automated tools

Visual development tools: rapidly build interfaces, reports etc using visual tools e.g.

Visual Basic, Powerbuilder and instantly test the look of the design (development and programming environments)

Embed AI into development environments use of intelligent agents (programs) residing in a

computer to carry out developer’s instructions to create new systems