I started reading a very recently published book. I don't want to mention the name of the book, but it is a tome targeted at "application developers." After reading a small number of paragraphs from the book, I had to check my calendar to see whether this was 2009 or 1995.

Some choice sentences from the book that just grabbed me right off the bat:

• "Software applications should simulate (model) the real world with close affinity to the problem domain."
• "...the average developer should spend 40 to 50 percent of his or her time in design and not writing code."
• "Similar to comments and just as important [emphasis added], the design documents a program."
• "An artist does not start with a paintbrush and a canvas. There is considerable preparation before painting can begin. ... Similarly, developers do not simply start writing code. The requirements analysis must be undertaken, a design drafted, the prototyping [emphasis added] of class operations, and only then, finally, the implementation."
• "The goal of TDD is simply to be a framework for addressing customer requirements with software through an iterative approach to testing and coding."

For me, one of the most illuminating benefits of all this up-front emphasis on design seemed to be realized in the brilliant class diagram for a simple retail banking system. It looks something like:

  Employee <|---- Teller  <------  Customer
              |
              |-- Manager

The power of the "real world" comes alive! This ingenious class diagram existed to support building the following code:

static void Main(string[] args)
{
    Customer cust = new Customer();
    cust.Teller = new Teller();
    cust.Deposit();
    cust.Withdrawal();
}

Per the author, this code "validates" the design.

I'm speechless. (Well, no, I'm fingerless, or something. There must be a better word for being so flabbergasted that you can't start to type a response.) I could rail on this book to no end, but it would only draw attention to the book (and you'll note that I'm not providing a link to it either).

posted by Jeff L.  # 3/26/2009 11:44:00 AM Database TDD Blogs