This week we continue with sample essays from my various books. The topic this week is taken from the beginning of Exploring Requirements, Volume 1.
Some of our readers would readily agree with the need to resolve the ambiguities in requirements, but they would argue the problem is not with the techniques, but with the technicians. In order to do a better requirements job, they would claim, remove the people from the process and instead use a methodology. Indeed, their preference would be a totally automated methodology, with no people in the development process whatsoever.
When we started teaching software development in 1958, there were few organized development methods. Today, however, packaged methodologies flood the market and almost everyone who develops software has some sort of organized process. For many years, computer-aided software engineering (case) and computer-aided design (cad) dominated the news, both promising to eliminate people from the process. More recently, the Agile movement seems to have rediscovered people, and they are seeing the need for a book about "people-oriented" tools to support their approach. But regardless of the approach, it must ensure everyone gets the right requirements, and gets the requirements right. Won't automated tools do the job without people? We think not, and the story of the Guaranteed Cockroach Killer will tell you why.
1.1 CASE, CAD, and the Cockroach Killer
For many years, a man in New York made a living selling his Guaranteed Cockroach Killer through the classified ads. When you sent your check for five dollars, he cashed it and sent you the kit shown in Figure 1-1.
Figure 1-1. The Guaranteed Cockroach Killer kit. All you have to do is place the roach on block A and then strike it with block B.
The instructions read
1. Place cockroach on block A.
2. Hit cockroach with block B.
If you follow these instructions, you are guaranteed to kill the cockroach. By rights, there should have been a third instruction:
3. Clean up mess.
Quite likely, nobody ever needed the third instruction—which also meant nobody could collect on the iron-clad guarantee.
Now, what has the Guaranteed Cockroach Killer to do with automated tools? One case document told us case tools are comprised of three basic application development technologies:
1. analysis and design workstations to facilitate the capture of specifications
2. dictionaries to manage and control the specification information
3. generators to transform specifications into code and documentation
In our experience, "analysis and design workstations" resemble block A of the cockroach killer. "Dictionaries" resemble block B. If you can somehow figure out the specifications, the workstations will "capture" them and the dictionaries will "manage" them. Once these two steps are done, the generators will clean up the mess and provide your product.
These automated tools are guaranteed to do their job if you simply do your part. This book is about doing your part: getting the roach on the block, and convincing it to stand still long enough for you to deliver the crushing blow.
Whether it's roaches or requirements, the hard part is catching them and getting them to stand still. Generating the code and cleaning up the squashed roach are messy jobs, but in a different way than the first two steps. That's why we think you'll still need the tools described in this book. Not only that, but the better your automated tools, the more you'll need our people-oriented tools. You can see why in the book sample at Smashwords.
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