computer-aided software engineering (CASE)

The use of computer-based tools to assist with the process of designing and implementing computer programs and larger software suites. The acronym CASE also stands for computer-aided systems engineering - the use of computer-based tools to assist with the process of analysing manual business information systems and designing new computer-based systems to replace them.

Computer-aided software engineering (CASE) is the use of software tools to assist in the development and maintenance of software. Tools used to assist in this way are known as CASE Tools.

All aspects of the software development lifecycle can be supported by software tools, and so the use of tools from across the spectrum can, arguably, be described as CASE; from project management software through tools for business and functional analysis, system design, code storage, compilers, translation tools, test software, and so on.

However, it is the tools that are concerned with analysis and design, and with using design information to create parts (or all) of the software product, that are most frequently thought of as CASE tools. Such tools arose out of developments such as Jackson Structured Programming and the software modelling techniques promoted by researchers such as Ed Yourdon, Chris Gane and Trish Sarson (see structured programming, SSADM). In this narrower range, CASE applied, for instance, to a database software product, might normally involve:

Modelling business / real world processes and data flow Development of data models in the form of entity-relationship diagrams Development of process and function descriptions Production of database creation SQL and stored procedures

The term CASE was originally coined by software company, Nastec Corporation of Southfield, Mich. GraphiText's successor product, DesignAid was the first microprocessor based tool to logically and semantically evaluate software and system design diagrams and build a data dictionary.

Most of the early, graphically focused CASE tools specialized in either process (program or module) design, such as Excelerator and ADW, or data design, such as Bachman, IEW and IEF.

The early CASE tools focused primarily on creating and analyzing graphical software design representations.

CASE tools were at their peak in the early 1990s. The three giants of the time were Atlanta based KnowledgeWare with their IEW (software engineering) and ADW tools and Texas Instruments with their IEF tool and Nastec Corporation (later merged with Transform Logic Corporation) and their DesignAid and LifeCycle Manager tool suites. These tools were full lifecycle and included Upper CASE and Lower CASE (see below).

With the decline of the mainframe, AD/Cycle and the Big CASE tools died off, opening the market for the mainstream CASE tools of today.

Some typical CASE tools are:

Code generation tools UML editors and the like Refactoring tools QVT or Model transformation Tools Configuration management tools including revision control

CASE tools do not only output code.

database schema data flow diagrams entity relationship diagrams program specifications user documentation

Sometimes CASE tools are separated in two groups:

Upper CASE: Tools for the analysis and design phase of the software development lifecycle (diagramming tools, report and form generators, analysis tools) Lower CASE: Tools to support data base schema generation, program generation, implementation, testing, configuration management