This is the fifth in a sertes on rapid appli- cation develop- ment (RAD), a development methodology de- signed, to yield much faster re- sults than tradi: tional methods. Rapid applica- tion develop- ment, as I've said before, is a new life-cycle process that harnesses the major increase in productivity that can be achieved by small tešms of highly motivated devel- opers using integrated computer-aided software engineering (CASE) tools. Al- though the success of RAD is primarily due to innovative management tech- nigues (to be discussed in future col- umns), advances in applications-develop- ment, technology also play a major role. An important; component of the RAD nl —- Ra Mi o : a A aa ii — gre E' za k rič nalet x . A Pavi Ce! ; O A k sta SiEVA ui ne onih rea a Ee si oe k a ua ae žiro JEM: Možni. naj a a si ote s dj že nie dei Fu ei RAMI Mai m a aa — gi ge za ee ae A | pake de l ! A a ne - ij ria ie sa piš ti ; j LE m -. ji di db za . i Ž 3 Č 4 | d, a dla > napi ; i AH Me peni ft Rp. V iz , pe ijet" je HUJE eration language technology and move directly to the next generation of dr tools—integrated CASE workstations closely coupled to efficient, desktop code generators. CASE tools must have certain charac- teristics to be effective in RAD life cy- cles, but many of the CASE tool sets on the market lack these characteristics. At first glance, the tools appear spec-: tacular with their flashy graphics, but they fail to incorporate some of the most important features reguired for entire life-cycle process, an integrated code generator capable of generating 100 percent of the code for an applica- Advanced CASE Facil Analysis | ——aA MWorkberich | Workbench j m IH — pO WEEKNAPPLIGATION DEVELOPM [PP jprieo rece MM ools a Must for High-Speed Development tory. When the design is coordinated and approved, it will reside in the life-eycle process is the use of integrated CASE (I-CASE) tools to develop entire vedi sa F a pu applications from design specifications. Small teams of analysts are intensively trained in the use of I-GASE tools and in a methodology optimized to achieve high-speed development. As shown in the figure, I-CASE prod- ucts incorporate separate workbench components for each aspect of the appli- cations-development; process, including strategic planning, analysis, design and code generation. Additional components support documentation generation, data- base generation and project management. The front-end planning, analysis and design components of these products are closely integrated with the back-end code, database and documentation-gen- eration facilities through the use of a common repository of design specifi- cations. Specifications developed by individual designers are stored in a personal repos- itory on the PC. Specifications from multiple project analysts on a LAN are consolidated in a project-level repository aecessed via a file server on the LAN. Design specifications that are common across (he organization are stored in a Carporate-level repository on a central ine. in an increasing number of corpora- Uons, all the EM of LCAŠE. - products, including the code generator — are being run on desktop workstatjons. These tools provide each workstation z ( | user with Customization, powerfu] |... Braplilcs, project] ordin: oa, MES ; zs intelligent operati evel coordination and The most advanced CAS used for RAD incorporate features such as "ed, desktop code generators. deja ba are capable of generating highly effi Cient code that can be used without per- lormance penalty in a heavily loaded | transaction-processing environment, Some information-systems organiza- lions that have been using third. ener: tion lang a£es such as COBOL zati choosing to lea (rog current, fourth-gen- GC: individual-Level pese, % Facility ona PC PC-Level 2 | ee Design Analyzer Project-Level Consolidation Analysis and Management HU PojectLevt. UN Pepositori . Project-Level Facility ho PELA On aLAN The most advanced CASE tools used for RAD efficient code that can be used without in a heavily loaded transaction. The meaning represented by diagrams and their detail windows is stored in a repository —the heart of an I-CASE sys- tem. The repository steadily accumu- lates information relating to the plan- ning, analysis, design, construction and, later, maintenance of the systems. An integral part of repository-based systems is a design analyzer, which en: sures consistency among the different ; pieces of knowledge that reside in the repository. When a person using a workstation en- RAD. Among these are support for the ': , ters new information into that worksta- i tion, the design analyzer checks whether (it obeys the rules and is consistent with what is already in the repository. ae vak V" 4 Mi 1 ME MAM bu pa bi bi a im BU il ba? dj ki ] diti j [ h i k 1 ; aj.R ' HE ai ih k la j ži he s | i i zd, i | h f ji nji ife (ua NE Te! Vr ui m ' buč li | i hi Ja aka! Pri..." s -. je, Hi 1: sutit kah oba di uka A sd ' ME! Kr di Code- | Generation .. Workbencn:'. . Design Workbench PC. en vi Pepositori Corporate- Level | Consolidation and Analysis Corporate-Level Facility KOM On a Mainframe. ; |, can generate processing environment. tion and support for a life-eycle process that is optimized for high-speed develop- ment. The manager of systems develop-: ment Meja select tools that, can su pport - RAD life eycles; otherwise, devel n zajemu will be low, no opne : principle of CASE is that, whenever. possible, diagrams are used as an aid to rus thinking. The systems analyst, uses . front-end workstation components . ileg aa SAGE tool to define de- Sign specifications by means a- /' grams, These h JA Normally, an individual or desigi team is not familiar with the snuie set of designs in the project-level repository B: the corporate repository. When an in- prodal starts to create a design, he Or ste will extract the information in the project-level repository that relates to | that design. The individual may, for example, ex lay, for example, ex- slej a portion of a data PMeliHo may eSigning the detail of : hat ' 'is already sho tail of a process that am se di je own in a higher-leve re teracting with the C ASE tool. poo byin- sentation. He then ka ea srk eh planning informatio ji | present largely independently f Gi pev | systems, data models and data fuga $ rePolory. Bi bo kev detalled designa and prs a Ve | ; When the deajan la rana. € Pe o kada da structures. it can be Consolidated uta se: kiosk f 1 | | ma it JANVARY 22, 1990 project-level repository, where it is available to other designers in the team The simplest CASE tools are little more than diagramming aids—word processors fer diagrams. They simplify the drawing of diagrams and enable - them to be modified guickly and kept ' up to date. Most CASE tools incorporate stage. a design analyzer, which detects logical errors and inconsistencies at the design More sophisticated CASE tools are re- guired to support RAD. The tools should f: with this level of integration. provide integrated support for each of the four stages of development: plan- |: ning, analysis, design and construction. An I-CASE environment provides an integrated set of tools for all phases of the life-cycle process. The term "I-CASE" should be used only to describe products In an 1-CASE tool, the front-end work- ' benches and the code generator use a common repository to generate program code, database code and documentation performance penalty level. ' The integrated CASE tool should do and provide testing tools; and generate database code and job control code so ed when design changes are made. H MI: | doza IME li ta o ji er EMA, | a ji k; NI ! s sadi . k JE. ši | yi 4 gubi j E | 4 | ka ' Ha i r u Bit [4 im A Prototyping is an important part of mo the RAD life cycle. It is essential to show the users what they're going to 4 ' get, allowing them to react to it. The - RAD tool set must include the INNe prototyping capability to create screens and dialogues guickly and to modify | them while interacting with users. The ability to generate code, test it, modify it guickly and regenerate it makes RAD prototyping different from conventional prototyping. With RAD, the evolving prototype is not discarded but is part of the final system. — This is an essential element of RAD. The prototype should become the final ', system. It should deliver the machine performance, reliability and other fea- tures reguired by the final system. Next week's column discusses the need for a new development methodolo- gy and shows why RAD technigues pro- ' vide far more productivity than the con- - ventional development process. B - The concepts embodted in RAD are de- seribed in a new volume in the James " Martin Report Series. For more infor- mation on this volume, call (800) 242. 1240. For information on seminars, ; contact (in the United States and Can. ada) Technology Transfer Institute 741 10th St., Santa Monica, Calif. 90402 (213) 394-8305. In Europe, con- EINE incs., LADO 9BX United Ki n (0524) 734 505. a that the program can be guickly execut- for the entire application. The code that - is generated should never be touched by maintenance programmers; all mainte- | nance is performed at the specification the following: facilitate the rapid building and modification of prototypes; generate system documentation; generate test data