0174 - OpenMPE
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1. this separation makes maintenance far simpler You do not have to be the originator nor have any written manuals present to be able t isolate a proniom piece of logic and fix it And in development e accomplishment of a logic object or process definition means that you need never handle that code again Contrast this with traditional programming in third or fourth generation language Construction of large and complex programs tends to be an iterative cycle of edit compile until clean add more com aay ven parts of a program that are running OK get compiled again and again Sometimes the subsequent re editing messes with code that was running satisfactorily Once again it s pomoi out that the chief beneficiary in the end is the user who gets a better response from DP for maintenance and new system development PROTOTYPING We now leave the System Inventory at least in regard to changing its contents But Prototyping a proven technique employed by many for verifying design can participate in the SI as well in our ideal CASE environment Pa If we did not get the look of our system right using the Data View facilities we can generate a proto application and actually ran the application When does a prototype stop being one e answer is probably when you feel like the design is nearly finished To truly proto what the finished application will look and feel like and picture what a day in the li 8s of the user will e2. toolset you see here figure 3 is oriented to a total application development environment In this diagram the CASE tools are visualised in a case and tidily packed away This has no bearing on the ordst you might use them in It helps you to see the interaction between each component to e RAREN Sa SS X res Rea 3 232 aae ons aa ye RS ROPER SOS lt 3 SaF RA S SERS AD o ae SS KEA aren TEPER ORN E RESISA eS h Se Sat a SEN s N NT a NOAS SNS COON EERE OR ONCE SB BB noe a Seas sit s EN x h SAAS oe oS on NA SS a PRAT NNN ne ee ww ot S s ee ER RRA m Te ESSA Ex o BOAR So DARS Ponce comes TENANE ASNS eae s Pee RINN SN 3 SY SN Sana EANAN on Se a ASAN RNS NS SAY ee Bcc Sees oe 2 SEAR Sara V NE S NSN TF L Se SS Sans X RENSES Bese gt REAR S AENA ANN ERIS eo EA ENE RS OAOA n a aaa n Pe ER EERENS od Baise gt TONTIT T TETTETETT TETIT EEIEIEE A onia RE oS nt Pesce cre Big ts GR N ee Pe Tat mis tg B RRR ENS A e AAN ESS PEREA ARAN S AEN Figure 3 CASE Toolset CASE A Way Out 0174 7 DATA ANALYSIS Sometimes called front end CASE tools these have been around for some time Used to analyse the behaviour of data in an existing or planned business application they help the development professional s understanding of the future design and data management requirements Large installations especially mainframe users tend to favour these products m
3. At the other end of the spectrum the most popular data analysis PC based front end is around 8 000 per co and a full application development and documentation environment can be had on Phe HP4000 for just 35 000 P The cost of the tools is of course offset by the gains in productivity and the com cuve pavantage to the corporation of having high quality and maintainable systems available aster CASE is here and it s growing in importance The signs are in the industry that it is going to reach all of us very soon and very pervasively 6 Summary We ve reviewed the pressures on MIS to upgrade the quality and service which is its responsibility and we ve seen how executive attention is becoming focused on software development productivity as being at least part of the problem where it exists One of the possible strategies to help us drive towards MIS quality and service objectives has been examined up close and one ideal set of tools has been proposed The ideal set of tools would transform our development center from a craftsmen s workshop into a professional software engineering center with consequent advantages already enjoyed by engineers in other disciplines And finally we have glimpsed a few of the developments relating to CASE in the computer industry which augur for a healthy period of penetration and growth for this technology Attendees are invited to discuss the CASE approach further at the RAET Software P
4. CASE A Way out of the Software Trap Geoff Davies RAET Software Products BV The Netherlands 1 Introduction One of the hottest topics in the computer industry today is CASE which stands for Computer Aided Software Engineering or Computer Assisted Systems Engineering Is this another meaningless acronym you see for a while that disappear in a short time when the excitement dies down e acronym could disappear but the concept will certainly not go away because design and construction of business application systems is so vital a dimension of commerce and industry today that our profession finds itself under increasing pressure to behave as Engineers Engineers today are assisted by computer technology in the design visualisation manufacture testing service and quality control of the products of their discipline such as bridges buildings automobiles weapons satellites computer chips and so on The terms CAD CAM Computer Aided Design Computer Aided Manufacturing and CIM Computer Integrated Manufacturing are widely known So it will go with Application Software development CASE is the term rapidly gaining acceptan e for the automation by computer of the Software Developmcat process Automation is being hailed by many as a way out of the Software Trap the trap we find ourselves in when we can t make vital new systems quickly or well enough because of the burden of holding together inadequate systems develo
5. L code is still maintainable second distributing applications based on a 4GL inevitably leads to high charges for runtime systems third distribution of compiled 3GL code gives a large meagure of protection against copying of proprietary source and reduces size of application libraries on smaller disk systems A fundamental assumption here is that because the CASE tools are integrated the Code Generator can read the specifications from the SI The Code Generator makes more than just executable code it should also create source code data management schemas initialise databases build screen forms e g VIEW write the linking job control bind message and HELP text files into the whole and act on your instructions for organization of the executable libraries USL s etc A number Pil benefits accrue from the CASE Code Generator Reliable and correct code ener oes not have to e 0 specifications n o be consequen fhe old cycle of edit compile over and over becomes less prevalent CASE designers don t feel the need that programmers do to get ane program perfect before going on to the next one In the CASE environment you could design for weeks and never generate or compile in all that time Then as you get to prototyping and refinement you begin to need to generate It becomes possible and I have seen it that contented design staff schedule all their generate compile activity for the back shift It s more con ucive to good d
6. This can only lead to trust in MIS and more satisfied users S Industry Trends We shall now review recent developments in Computer Aided Software Engincering and see whether any trends are emerging Technology CASE workstations driven by proprietary CASE software are expected to become a growth area Analogous to CAD workstations the CASE workstation will use icons to ease the selection of objects for de activity and windows to permit rapid navigation through e toolset and to run te and design side side Some engineering workstation vendors are already producing CASE workstations for IX systems Workstations which are full compere with the target environment are today quite common els and the new HP 3000 LX mod could be considered to be development workstations for H corporate systems i CASE A Way Out 0174 15 Start ups Business Week reported in May that the worldwide market for CASE tools could hit 2 ion in 1992 and in the US alone 800 million It s no surprise then that there are many people Siting into the act In the same article a San Francisco consultant sees two new CASE start ups a day and an analyst reports that he knows of some 100 CASE companies mostly less than two years old and most funded at more than 1 million Perhaps we ll see the same explosive sort of growth that the micro started Standards It only becomes interesting to attempt to establish industry standards for any new technolog
7. ce code to locate where changes must be made Because our tool has a very active inventory the effect of changes proposed can be detected and propagated quickly Documentation of design long a despised task of programmers becomes a task of attachin an annotation fe our objects describing only what makes it different from any other similar object The SI thus forms a complete design specification for the target Application or in manufacturing terms a B of Materials And like any manufacturing product data management system you can obtain very useful information to aid decision making where is this data field used what if I extend its length bill materials can be exploded to show down to the lowest level all components and sub assemblies Productivity gains in analysis of change effects and in re use of standard objects are quantum Factors of 10 to 20 in this area are not uncommon A designer familiar with the System Inventory becomes concerned only with differences in objects designs produced by others are thus accessible and transparent making atenance a process that is not as arduous as poring over listings Breaking a problem application down to detect a fault requires no program libraries no UDC listings no programmers notes you break it opea in the System Inventory and examine the component objects self contained pieces of the design Because the whole design is available to all design staff divisio
8. ctive and where the properties of a data item are part of the object definition we need to know a whole lot more Added to the usual descriptive information in the DD such as Identi nam and etc we also want to define other properties that will be A A fo our application So we also want to know headings for use in reports and displays a one character code with a long name might justify a short heading security or ways to identify create update read access anges for automatic input validation tables again for input validation ting for input and output locking if res to _ prevent simultaneous update by two transactions defaults when not filled in HELP to display at CASE A Way Out 0174 10 input if the user is uncertain structure if an entity is part of another entity sub fields if an entity has them This is not an austive list The important point is that in our ideal toolset all of these are propertion of the data item and you do not have to code them to have them available in your application If the data item is accessed all its properties are automatically there Because defined data about data is all in the inventory useful information can be given ine or line to the designer Decisions Support is given by cross referencing vhfrgased search and retrieve Defining new data objects is rapid with same as excep ac Maintenance happens faster and with better results because the designer mak
9. ductivity Consortium They have an invited group of CASE vendors called the Guest Systems Council and jointly ney are attempting to formulate complementary strategies for their future mutual benefit The last press statement I saw was optimistic but nothing concrete had emerged Education MIS is traditi sally adverse to risk and as a consequence is not yet ready to embrace the new technology Few companies want to be pioneers and few in corporate MIS want to lead e way for their colleagues As Computerworld put it we need a hero in e programmer s shop However a growing number of CASE evangelists such as T Capers Jones James Martin and David Yourdon are defining the CASE environment thoroughly and some excellent publications from some of these authors are available There will probably be an increase in the exposure of computer science students to CASE methodologies Cost There is a huge variance in the price of CASE tools just as with 4GL s and databases depending on whether you re an I mainframe user or a small mini user CASE A Way Out 0174 16 A total life cycle CASE environment recently announced for mainframe IBM by one of the Big Five accounting firms includes an IBM PC based methodology front end at 50 000 for a site license a design interface for filling the repository at 7 000 per networked micro Worsstation and a generating implementing back end that costs a hefty 200 000 for a single license
10. echnique employed a definition of the error handling e g display message re set work areas the work aroa or common areas that the logic accesses linkages to other processing logic objects depending on success or failure and other possible properties Of conne the actual data manipulation and calculation logic itself is also a property of e object In any CASE environment it is almost impossible to eliminate the need for a high level or macro definition language Our ideal CASE toolset includes an interactive editor to allow yop to enter new or copy other logic same as except as a starting point The tor must include features to ensure at the logic is syntactically correct and that we work with real data defined in the DD CASE A Way Out 0174 12 The CASE mictnodo Oby relieves much of the tedious coding chores from the designer through its Data Dictionary Data View and Structure facilities So it s probable that 80 of the design coding effort will be expended in this part Our CASE Process Definition Language must therefore provide a very high ine of macro capability reducing to a few keystrokes what normally requires a substantial coding ort The highest skilled analysts in your installation can preserve in a _ re usable form their skill for access by less sxperienced personnel Because our CASE processing puts a ee aroun a piece of logic it becomes simpler to read it understand it use it and earn from it Again
11. ected buildings the way we put application systems together we would start from a sketch plan hand craft the building from the roof down every room would be a different size shape height we h wond make all A fittings aparea instead a using standard ones express surprise when the owner said they wan oors not 3 and finally we would hand it over and say use it for a while and tell me what ye think if ite not quite right I can make some small adjustments When we th it was all finished we would get around to drawing up the real plans if we hadn t started another project Maintaining our building would entail going into the building and rearranging it until it e right Now let s use CAD CAM as an example Wh can deny the value this has been to the engineer who can now construct at a workstation a complete specification for a machine anspect and adjust it before having manufacturing put it into production He doesn t tell the computer every item of detail of a gear wheel for example He tells it he wants a 32 tooth spur gear of radius 4 25 inches and then adjusts it and moves it around cers quickl me familiar with apnar new tools in spite of resistance by MIS who I have seen challenge the competency engineers to select and use them To conclude this part let s look at our graph again Figure 2 and see how it might look with an engineering approach to development CASE A Way Out 0174 5 We have a flatte
12. escribing all structures processing messages and tt seroens reports and data dictionary is asking for a System Reference Manual It s always up to date Calling for menus screens and report layouts annotated with the validation rules ranges and associated HELP text for all input fields and action screens is asking for a User s Manual And it s also always up to date DP staff benefit that burden of guilt for incomplete documentation lifts from your shoulders Your client user benefits also machine produced documentation is able to be customised and formatted I ve seen very smart manuals produced with corporate logos and other frills using a laser printer and CASE documentation tools PROJECT MANAGEMENT These tools are not exclusively the preserve of CASE but when you run the rest of you development environment so well w y not underpin it with an integrated toolset that helps you maintain control over large development projects and maintenance All project management tools include a Critical Path algorithm cfining the shortest path between the start and finish points and many include cost control and resource management facilities Integrating Project Management to the rest of the toolset means measuring progress accessing the SH aad determining if required stages have been passed yet It also means at Metrics can actively employed to determine based on pr vious performance when a project will be completed
13. esign to simply work with the interactive tools through the day bypassing the edit compile programmer s cycle with it s trips to the printer sessions with spook and just one more small change and it will be right Less erratic unscheduled and CPU intensive activity makes for good response times TESTING The automation of Testing is a late emerging part of CASE There are some tools available that allow you to automate an interactive terminal session that signs on enters transactions creates reports deliberately makes mistakes and so on according to your scripts and then gives you a report on what was different from the last time it did it Specification of standard test procedures like this is vitally interesting to software package developers or to those with colossal user populations You could check for code that was never entered why do we need it Maybe our test was inadequate or we have a logic error and try afl the ridiculous values for input I never would have expected a user to enter minus 5 for the month Another interesting area we want for our ideal toolset is an extension of the Data Dictionary to describe the intricacies of data behaviour in the finished application This might for example describe the usual distribution of number of order detail lines per order header the usual distribution of letters in the NAME field of a NAME amp ADDRESS group A test data generator would then construct
14. ession is that MIS who are gerose to be able to provide the total service for users simply are not sufficiently professional in the delivery of their service User to MIS communications shouldn t the responsibility rest with MIS to behave as it and CLARIFY a user s requirements before a single line of code is written Scares of technical resources where is the greal problem is it programming or analysis IS planning and estimating ability other departments engincering manufacturing istribation Bie can submit well managed business ah F project Ca S why can t MIS MIS development productivity little gain has been made in development productivity in the USA in recent years Few can fren measure it im fact system development is wide regarded as the last uncontro business activity and one for which few benchmar measurements exist MIS quality control contrast the quality control procedures if any of the MIS department with those of manufacturing and there is a yawning gap And that should come as no surprise QC in engineering departments is based on a rigorous discipline stemming from the recognition that ultimately customer satisfaction an safety will determine the success of the corporation MIS has only internal customers we have an informal relationship with our customers and they have only one choice of supplier But MIS can uild systems on which the business mus depend to survive with no es and th
15. et As with a manufacturing product data management system our CASE tools will allow us to keep all system specifications in one place where e developer s can all access it uniformly In terms of Data Dictionary this is not such a novel concept but for the other items it s quite uncommon up to now We will look at cach of the four categories of information retained in _ this repository shortly The System Inventory can only be useful if it is accessible interactively for system designers note that we don t say programmers Adding editing and manipulatin spect ications requires a very active interface comm referred to as the Designers Workbench A day in the life of an analyst or programmer changes radically when us such a tool You spend little or no time using full screen character mode editors the Workbench presents your SI to you in a formatted and organised way As soon as an item is added to the inventory it s available for another designer o use A good workbench will provide standard objects from which you can derive further standards of your own such as standard screen and report layouts Objects can thus breed through same as except derivations and the components a target application system can come together very quickly CASE A Way Out 0174 9 Progressively as you describe your design you can refine and enhance it Alteration of spect icaulons organised in this way is light years ahead of reading sour
16. full data bases based on the statistical information you pr lict for you to test One of the hardest parts of testing is to get enough realistically filled records to make all screens and reports look as they would when the application has been in use some time Or even to be able to estimate the response time of an inquiry application accessing a data base with a million records and a complex structure est data generators can do this CASE A Way Out 0174 14 DOCUMENTATION There are already a number of tools on the market to help us do what we least like doin ocumenting our systems But they rarely are able to shine light on i behind logic that they scan Our System Inventory is self documenting e designer is disciplined more to create a small amount of descriptive information when creatin Processing objects where he is outside of the boundaries of pre structured OF special purpose objects All the re structured and special purpose objects screens data elements reports transactions menus have such a defined Igic and ol ar that further manually produced documentation is redundant An active System Inventory therefore carries all its documentation within it The CASE toolset only needs to provide access to the design for management reporting and designer review This is accomplished by reports and inquiries and is an application that should offer choices of levels of depth and complexity Calling for a full set of reports d
17. ge prablem report facility entry point to users on all application systems A further issue arises here and that is controlling the versions of software in use especially in a distributed systems enyironment Change control should therefore take account of the version in use at the point where change is needed and being aware of the effect on other current or future versions By dealing with the very natural process of change in a professional pnd engineerin mode we enhance the quality of our service and gain greater confidence from our clients CASE A Way Out 0174 8 METRICS Repeating the earlier assertion that productivity of the development center is virtuall impossible to measure objectively we should look for tools that will help with this our development resources are substantial There are many HP 3000 users in the world with multiple development centers with many development staff at cach site Our ideal integrated CASE toolset will permit us to measure ovr production and prodacenity is is very important if we want to collect project progress information ut we come to that later Here we raise a concept that has not yet been mentioned Object Oriented Programming This concept is emerging in a PC development environment we sce an object oriented interface in the HP NewWave environment and the famed Macintosh interface At the gat of me eion you were asked to forget about lines of code and programs but to
18. gramming to make corrections Sad finally establi g om paper or in code how it all works and what it means for MIS and users Maintenance Does it ever end The amount of maintenance depends on how good a job you did in the first place in terms a NEED for maintenance and it design program test maintenance doc TME Figure 1 Traditional Approach CASE A Way Out 0174 3 Figure 1 shows a theoretical model of a development project using traditional approach and the four stages altho there is no sharp line Fpetwech iget m Srhe area under the curve would represent the total investment made in human and other resources in the project This graph emphasises that traditionally little resource in total goes into design Why is this Because there is little that one could do to significantly refine a design to make it more useful of and report layouts as we go So the once you have a few flowcharts a list of data items and some screen Let s get on with the programming and of course we tend to design of cost is ind in programming Testing and documentation are perhaps given MORE weight than is real in the traditional DP world It fends to be a haphazar ac ivity the programmer tests his own programs and documentation follows la ll we don t like to write pages of notes we think the user t reject the system until more changes are made course if we got the design at wrong up front we could be a very long time putting
19. hat these Lamia are I tagile things Quality Control is closely linked although we don t tend to in at Most old hands have had the experience of a minor change causing massive disruption to a critical system It s all too tempting to think we know all we need to and make a quick fix that later turns out to have an effect we did not expect The problem is exacerbated with interpretive code environments we often want to try it and see in a live usage Even when a backup is available to undo the damage the disruption can be earful So a management information system for MIS itself is needed whereby procedures are in place to control changes to sensitive systems To return to the manufacturing analogy change to established design normally goes through an EC Engineering Change approval rocess with QC Engineering Marketing and Shop Floor inspecting the change and commenting on or planning for the effect of this Our ideal Change Control system will include forms for submitting problem reports and change requests a submission and registration procedure a design review comment and approval procedure quality assurance procedure by which sign off is given that impact analysis check on relational integrity within programs testing documentation and user advice have all been done and a release procedure ese procedures can real time and continuous in a DP shop there does not even have to be any paper Why not give a chan
20. in terms systems Object oriented development is more encompassing than programming but the idea is the same Development activity and progress is easter to express in user oriented terms to the users themselves why not measure in the same terms Our CASE tools will help us develop objects such as screens reports transactions menus database definitions and so on Lets measure our progress using those terms Integrating metrics to object development means that our Metrics module logs resources expended in accomplishing the development of a unit For example let s take a screen as an object of development Metrics LS for the screen the total sign on time programmer resources CPU cycles for design cycles for forms generation and also can study the make up of the screen to arrive at a complexity measurement you want it can also identify who did the job Now this is not such a horrifying idea in most other disciplines these measurements are indeed done Comparative data on the performance of individuals may be more draconian aa re could bear but of classes of personnel trainee advanced expert may be very useful Commercial software specialists who do devclopment work by contract would find this very useful as a basis for charging as indeed would internal corporate development centers who would then have a practical basis for cost distribution to client departments SYSTEM INVENTORY Now we come to the heart of our tools
21. ing a data change can inspect the tipple effect of that change Much maintenance finished applications can be carried out simply by selecting and modifying a simple data entity definition for example ranges editing prompting HELP The ultimate beneficiary is the application user data items are presented prompted and handled more as he intended when he first explained to the designer of the existence of the items He gets consistent treatment from his application because editing validation prompting annotation are always the same rather than a different programmer s interpretation each time DATA VIEW Defining the Data View is the process of telling your CASE toolset how the User wants the application to look and to some extent feel From the on line viewpoint this is the layout of Screens the way exceptions and errors are handled online the nature of user prompting and menus For off line operations the layout of reports is part of the data view And navigating through it all is also part of Data View What s different from traditional programming is that we store standard and special ata Views in the System Inventory as objects for managing and maintaining All the facilities of the Data Dictionary are available for constructing the Data View headings edits standard data validation and so on And because we ve defined data entity relationships associated data items can be mapped into screens and reports toge
22. is true if the other tasks surrounding the programming design esting problem resolution editing take the same amount of time anyway Understanding the productivity average for your development center is important if you are to fe able to truly now that you have made im rovements Knowin pr uetivity by fonction and by individual personnel can be very helpt in determining what resources to apply in a development task How useful would it if you knew the average time it took a skilled analyst to produce a transaction of medium complexity when estima time and cost for a new project And the time it takes a trainee programmer to produce a new screen display for an existing system including testing and documentation update Your manufacturing department has this sort of information relevant to their operation In all of the tools available to the HP3000 user today there are very few that help with design You can obtain PC based applications that help you understand the data and flow ra ta in business systems many even produce diagrams to use as a starting point for rogramming And yet it is in failing to get the desi j at the ve inning that our problems i 7 A_ business application maten aces all of its eee ad menus all its reports all its transactions data management activity and system management form a critical structure supporting the corporate activities Compare it with for example your head office building If we er
23. it right later And maintenance where 80 of America s programmers are busy as Wall Street Journal would have it just never ends Unless the documentation was comprehensive even through earlier maintenance we have a lot of code to read What we would like to accomplish is to get the curve flatter it makes scheduling easier lower it reduces costs and for the delivery point to be nearer to the start point ere are some ways to help this 4GL A fourth generation language can reduce the programming load 4GL s boost productivi enormously in_low transaction volume applications and also are very effective in rapi rototyping They have a great ability with data manipulation and for ad hoc report and quiry applications The penalty is paid in performance and in transactions with any complexity of data management RelationalDatabase Information retrieval intensive applications benefit from relational data management and the associated retrieval Bris BS easier to code with than Cobol Again e penalty is paid in high volume applications and you still need traditional or fourth generation language for full function application development Code analysers and restructuring There is substantial growth in this segment the advantage comes in making old code maintainable Obscure algorithms developed twenty years previously can be made readable or today s analyst Data Dictionary Implementing a standard data dictionary is a ver
24. left the enclave or pastures CASE A Way Out 0174 1 And indeed little has changed in that respect Today experienced programmer analysts operators and management are as scarce as ever which is good news if you are one of ese In our efforts to keep up with demand and to maintain quality in the delivery support and maintenance of business systems we have become a serious drain on corporate finances et seem to get no closer to answering fundamental questions about the service we provide y do development projects so often run behind schedule and over budget Why can we no repair software defects as quickly and easily as an engineer can correct hardware problems Why must important enhancements to critical business systems necessary for competitive advantage wait so long to be scheduled and implemented It s generally agreed that the reasons for this at least in the area of business applications are to do with the ability of MIS to take the expression of a and solve it with a computer based solution Among the reasons most commo cited User to MIS communications is poor MIS understanding of users needs is poor Users keep changing their requirements increasing the maintenance oad Good programmers are scarce MIS ability to plan and estimate is poor MIS development productivity is low MIS quality control is almost non existent There are many other possible explanations excuses but the overriding impr
25. n of work to specialists becomes a simple matter for example into screens reports processing structure Measurement of progress even in the absence of Metrics is facilitated countin components at least gives an objective measure Try coming up with a simple an repeatable way to estimate the percent complete of a source code program And of great importance programming style becomes minimised in impact The software Picassos amon Pis may Pie perturbed Hy that we believe that Pour own style is outstanding and want to leave our signature on our works of art but we can t stand maintaining code of others because they are never as competent as ourselves The wor elegance turns up frequently when programmers are describing arcane coding problems We will now examine the contents of our System Inventory and how it helps us produce better systems faster DATA DICTIONARY This is a repository of Data about Data Data Dictionaries have been around for some time most vendors offer one HP 3000 users even have a choice The Data Dictiona rops all we need to know about data in an accessible location and all developers use fhe DD to reduce redundancy and error in their use of data items The information kept here is fundamental or describing the properties of data items organisation defining relationships and physical describing for example disk data management In a CASE environment where re usability is a major obje
26. ntai you have to be able to go from tfansaction to transaction as the user would not by starting Data Entry under Formspec The user needs to see and you also what the screens and reports look like when there is data appearing in them In our CASE environment therefore you can check the izok in the Data View parts of the workbench as well as the prototype But for the feel you need to start the application rom the Operating System as in real life Which is why the proto is best made as the word intended not in some special make believe environment such as by using dBase but is in fact the first effort from the toolset and in fact is the first reviewable version from the code generator next As with verification of the look in Data View up to 80 of rework can be eliminated from the post delivery phase if you do this phase right And that makes us all happier CODE GENERATOR Ideally you should use the code generator to make the prototype because then it is a trae prototype Why a code generator Its not the only choice there are quite a few CASE environments today integrated to a 4GL But 4GL s often give real performance problems in h pepsaction intensive systems A code generator that makes compilable code gives you some ringe nefits CASE A Way Out 0174 13 First if generated code is recognised third generation language such as Cobol or Fortran then you maintain independence of development environment your 3G
27. ore perhaps because they seem to fit very well to relational data management The usual approach is for a skilled analyst to survey the user s application area capture into the PC the data entities identified and as much information as is known about these entities Progressively the whole story is built up including the logical organization the data the updating points the relationship to other entities the properties the entities editing type size and so on Gatput from these tools is typically presented in graphical form in entity relationship grams an ata flow diagrams Some tools are directed at specific structur programming techniques and produce diagrams in a compatible form Increasingly use is being made of the output directly accepting the entity relationship information as an initial data Phodel for y the as P Dictionary especially on mainframes CHANGE CONTROL Whether it s the introduction of a completely new application _or the adjustment of an existing system Change Control or Change Management is a vital aspect of controlling a lively development environment Volumes have been written about effective control of change and its impact on existing Management Information Systems Micro and minicomputer users are notorious for their cavalier attitude to changes in a running application Mainframe users have been in the business long enough and in a hitherto more complex environment to know t
28. ose systems can be grown and extended over decades to massive networks of thousands of terminals and enormous transaction volumes So I would suggest that we as MIS professionals whatever the size or budget of our department should decide firmly on a strategy to upgrade the seryice that we offer and aggressively implement that strategy while we still have a choice in the matter CASE A Way Out 0174 2 3 Strategies for MIS to reach Quality and Service objectives oct briefly we will look at some steps that MIS could take to approach the objectives of Quality and Service that are desirable if we are to be seen as an asset to our employers including CASE methodologies and tools There are many different ways of dividing up the components of a development project and of course most MIS deparfments have several projects under way simultancously The following four stages are a simple model and we ll assume that it s already been decided to pr with a project Design Visualising the finished lication analysi e data and flow er of data and setting out Rit programming g data management requirements Normally a pen and paper job one by an analyst Program Actually creating and editing programs in the selected language i and submitting a succession of E evisions to a compiler or interpreter until each program is finished Test and document Iterativ cedure of verifying that tbe programs work going back to pro
29. ped in the past This paper will explore the background to CASE the benefits it can deliver and suggest an ideal toolset especially with regard to the HP3000 Finally some industry trends are examined for a view of where CASE 1s headed 2 MIS Quality and Service goals under pressure The march of technology in our business has not diminished in any way the pressure on MIS to improve its performance in the delivery of support to the business activities of our corporate masters Everyone today is aware of the incredible price performance gains in the computer with a microcomputer being almost as common a feature of the middle class household as the television set Corporate leaders are therefore asking themselves why they do not perceive similar advances in the delivery of quali support systems for business activities It s becoming such a glaring deficiency that general business publications are examining the problem and liscussing the effects and possible remedies Our dirty linen is being was in public Are we doing such a bad job Corporate analysts say that on the whole we must be able to do better Data Processing was once a black tower where magicians wove their secret _ spells and spoke in strange langoa e that awed and mystified the tremulous user The minions omain were known fo Be fickle and some even had a reputation for blackmail the secret gine possessed by them would leave their employers paralysed if they
30. r curve with the earlier delivery of the system The programming phase is compressed because in an engineering approach rather than telling the computer how to do everything programming we concentrate on telling it what we want accomplished We then leave it to the computer to assemble as much of the design into our desired executable application system as possible We give the computer the task of coding the solution using highly re usable code structures How do we implement design on an HP3000 We have to select tools that will allow us t interact with our HP 3000 terminal as a computer aided design workstation and which wi interact with all the other parts of the development cycle giving us a complete software factory This is the objective of CASE Figure 2 CASE Approach CASE A Way Out 0174 6 4 An integrated CASE toolset In this section you re asked to forget about writin programs to deliver business applications Thinking rograms makes you relate to CASE at a level of lines of code and to do so is to be fetfered by tradition Instead think in terms of the systems you need to produce and of those systems as made up components and sub assemblies rather as a manufactured product might be Our proposed CASE toolset may not correspond exactly to how you might perceive the vital parts of an integrated software engineering environment There are many ifferent ways of representing a CASE toolset this is just one The
31. roducts exhobot number 1015 CASE A Way Out 0174 17
32. ta base s and or files naming the processing objects next section to be invok at the sockets in the transaction and the relationships between the transaction and the application and other transactions What you get automatically is management of database activity function key recognition and action correct entry point and initialisation correct housework at end management of a propriate HELP to the right point at the right time carri in from DD and DV and sensible error handling Its akin to selecting standard foundations columns bearers partitions and roofing when designing a house Now we benefit in design and maintenance by isolating system navigation and transaction logic problems or changes to parameters rather than having to handle source code and J Control Language Our user is happier because getting into around and out of a system is always e same regardless which system it happens to be Peculiarities and quirks can are sometimes amusing often downright annoying are a thing of the past PROCESSING Processing or calculation and data manipulation logic can also be reduced to components of a structured application suite The component or logic object is a self contained and re usable System Inventory item with associated properties e nature of those Bropertiss is_ defined by the designer but the properties include besides an identity a escription for the original and subsequent designers of purpose and t
33. tems built in traditional programming methods pore have a clear architecture or structure with the congequence that a great deal of effort goes into laboriously writing code to facilitate navigation menus related transactions etc and to handle the interaction of data management database and files manipulation and data precatedon or Data View What is odd about this is that almost all of this has been done before bat only sonig imes do we take the trouble to establish re usable code to make it easier e next time Enter CASE in which a catalog of standard structures for all standard programming logic is already available eliminating the need to program it This does not mean that you now have to manipulate Cobol with the aid of copy books CASE gives you once again objects which are pre programmed structures for System Management menu tree structures for example applications where the component transactions are defined and transactions themselve and batch These structures can be thought of as models that you select manipulate and customise through parameter settings Within each type of structure all the management is provided automatically by model in use Take for example an online browse through historical records e select a BROWSE transaction model and proceed to specify the customisation necessary to make it unique for our user This would involve naming c Data View s attached and the Data Management required da
34. ther i e groups of elements are presented together for input output Now we should also attach to our Data View objects some other information mainly a reference to special rocessing if any such as related item validatians for example three input fields might have to add up fo 100 and of course HELP describing how an what to do at a menu or screen is approach separates screen processing from the driving transaction and again makes maintenance easier by breaking fhe overall application into manageable chunks You should have tools in your Workbench with which to define and edit Data Views rapidly re use existing components same as except and with which to inspect and adjust the actnal appearance it eg screen painting You should never have to enter code inspection What are the benefits of separately defining Data View Because it s here that 80 of user acceptance problems occur then by reviewing your design ith the user BEFORE the tougher part of de ign begins processing you Can adjust e design even before the user s very eyes It is even worth considering giving the user limited access to this rt e design to make the minor adjustments or in the online guidance themselves HELP text ete m type gut CASE A Way Out 0174 11 STRUCTURE The advantage of CASE s object oriented approach is the separation of the desired application into components which are easier units to manage and maintain than programs Sys
35. y once there is a discernible movement to embrace that technology by _ large numbers of pone There are no standards e for specification of software design and no standards for peoducuviy measurement e IEEE has st ed for several years to come up with a single perfect measure of software productivity but few believe it is possible What is more likely is that the new CASE technol and object oriented design and pr amming will permit accurate measurement of development effectiveness but comparison o former methodologies will not yield any accurate figures because the old methods of measurement are so imprecise Alliances Recognition by the computer industry that growth is stunted by the inability of corporate clients to take full advantage of the power of new computers because of the maintenance ong development backlog has greatly accelerated the interest of vendors in having CASE cols available lowering the cost and improving the quality and service offered by MIS might make more budget available for more hardware purchases and growth in user populations can only lea to increased peripheral and capacity purchased Consequently we are seeing major hardware vendors and software companies teaming up and manufacturers of discrete CASE tools getting together Even major corporate computer users are invited to have their say In 1985 fourteen leading aerospace and detest contractors formed a limited partnership called the Software Pro
36. y real way to introduce some productivity making data definitions re usable by programmers on a team of maintenance programmers in the future reduces the amount redundant coding considerably Gonerators Code generators and report generators are a good way to re use programming done a somebody else Usually driven by a procedural language you can get skeleton or ever complete programs from a few statements CASE A Way Out 0174 4 The promem with all of these and the many other productivity tools available today is that few are integrated and there remains an almost obsessive emphasis on the program as an object of attention It seems to be overlooked that the objective is to build application systems that s what the business needs us for Furthermore how do we measure that we are in fact gaining in productivity at_all and to a sufficient degree that we can assert that our service is improving Development productivity as mentioned earlier is an almost immeasurable quantity The most commonly cited measurement is lines of code per day Two problems with this first what constitutes a line of code A line of Cobol A field defined on a screen A line of a DBSCHEMA Is a replaced or deleted line a line of code for produetivity ancasurcs What if I copy 1000 lines from another program for a same as except purpose Second if a line of Powerhouse code can do what ten lines of Cobol do am I ten times as roductive Is th
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