Author: Dietrich Kappe

Refactoring versus Rewriting

Dietrich Kappe, Monday, March 1, 2010 @ 5:09 am

Refactoring versus Rewriting
I started my first real Agile software development project in 1999. I'd been doing more traditional software development before then all the way back to 1980. I won't bore you with the details of those earlier projects, but my feeling was that there had to be a better way of developing software that didn't involve a senior technologist (me) telling a whole bunch of junior technologists what to do. It turns out I was right. :-)
But almost from the start I got pushback from other people in the development organizations I worked in that Agile development was horribly wasteful. They pointed to Test Driven Development ("all those tests more than double your effort"), pair programming ("two developers doing the work of one?"), and refactoring ("you're rewriting the software every time at enormous cost"). Of course all of these objections were borne out of a misunderstanding of Agile development, but of how their own software development processes actually worked.
The issue of refactoring was particularly mysterious to my colleagues. If you took the time and designed software properly up front, you don't have to do expensive rewrites. Of course anyone who has ever maintained code knows that this isn't true. All code, regardless of how it is developed, changes over time for bug fixes and to meet the needs of new requirements. If you aren't thoughtful about how you change your software, you can easily end up with a big mess.
If you are thoughtful about how you change your software and think about the sorts of "code smells" that crop up in your code over time, you end up making more fundamental changes, rather than adding a method here or a instance variable there. You might see that two methods are always called in conjunction and decide they should be folded into one method (a design win), or you may have extended your design and ended up with two parallel hierarchies of classes. You break the Go4 glass and pull out the Bridge Pattern to solve that burgeoning design problem. Through constant refactoring (or rewriting, take your pick) you avoid painting yourself into a corner as your requirements change.
The fact is that good developers are constantly redesigning and rewriting their code. Those same developers will tell you that the longer you leave problems before refactoring, the bigger and more expensive they become, until you might be better off just scrapping the system and rewriting from scratch.
Agile development takes this normal refactoring to it's logical extreme. Rather than doing a big design up front and then doing a series of expensive changes when they are inevitably found to be wrong, Agile teams accept that their design will be imperfect and then build comparatively inexpensive refactoring into every iteration. It may seem counterintuitive, but all that refactoring results in code that is cheaper to develop, easier to maintain (because it's easier to understand, change and debug).
Among professional writers the golden rule is that the key to all good writing is rewriting. The same is certainly true of software.

I started my first real Agile software development project in 1999. I'd been doing more traditional software development before then all the way back to 1980. I won't bore you with the details of those earlier projects, but my feeling was that there had to be a better way of developing software that didn't involve a senior technologist (me) telling a whole bunch of junior technologists what to do. It turns out I was right. :-)

But almost from the start I got pushback from other people in the development organizations I worked in that Agile development was horribly wasteful. They pointed to Test Driven Development ("all those tests more than double your effort"), pair programming ("two developers doing the work of one?"), and refactoring ("you're rewriting the software every time at enormous cost"). Of course all of these objections were born not just out of a misunderstanding of Agile development, but a fundamental misunderstanding of how their own software development processes actually worked.

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Software Development Software Development

Remembered: Claude Shannon

Dietrich Kappe, Wednesday, February 24, 2010 @ 12:38 pm

Claude Shannon

Claude Shannon

So, it's little Stevie Jobs' birthday today. Certainly he's been influential in the world of digital computing. But when folks wax on and wax off about how great some of these more recent figures in computing have been, I like to remind them of some of the all-time greats. It just so happens that that today is also the 9th anniversary of the death of Claude Shannon. Who is Claude Shannon, you ask? How soon they forget, or perhaps they never knew.

Well, in his masters thesis at MIT in 1937, he observed that you could solve Boolean algebra problems using switching and relay circuits. OK, think about what that means. Wait for it...yes, he invented the modern digital computer. In 1937. In a masters thesis.

It was all downhill from there, of course. He only founded the field of Information Theory (central to cryptography, computational linguistics, and pretty much any kind of digital information processing). Yes, the digital revolution started with him.

Oh, and he also laid out the field of computer chess in 1950, describing the different ways a computer chess program could be designed. Sixty years later, his roadmap for the field has been dead on.

So, the next time someone celebrates Stevie's birthday, let them know about Claude Elwood Shannon.

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Software Development Software Development

Post-Agile in the Game Development World?

Dietrich Kappe, Monday, February 15, 2010 @ 4:52 am

V&A Kanban December 7
Creative Commons License photo credit: Rich B-S

Gwarred Mountain over at Climax Studios has posted a very thoughtful blog post about software development methods and the appropriateness of Agile Software Development. I was ready not to like this article, what with the title and things like this:

If I have to sit through another meeting with some little "agile" toe-rag defending their train wreck of a project then I may end up forcibly ramming a kanban where the scrum does not shine.

But then I thought about all of those fresh-faced management consultants we've run into recently -- who have read a book about agile -- trying to teach us how to do it. Well, yes. I've had some uncharitable thoughts myself. Continue reading »

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Software Development Software Development

Why Computers are (aren’t) Better Than People at Playing Chess

Dietrich Kappe, Friday, February 12, 2010 @ 9:54 pm

It is very easy to misunderstand software and it's capabilities. Although people and software often perform the same tasks, they often do so in very different ways and achieve very different results. The results software can achieve are sometimes surprising, even amazing. But what computers can do is still quite limited. Making software development decisions based on an incomplete understanding on how software works, or drawing unwarranted equivalence between humans and computers, can lead to comical or even disastrous consequences.

It is with this in mind that I wanted to revisit one of my favorite topics: chess engines -- the computer programs that play a game of chess. Chess and computers were back in the news with a mainstream article by the mother of Kris Littlejohn entitled The Role of Computers in Planning Chess Strategy. Her son, Kris, helps current US Chess Champion Hikaru Nakamura prepare his openings for torunaments and matches and he makes use of various software (chess databases and engines) for this purpose. It's a well written article and well worth a read.

I've been an avid chess player for many decades and have also written a number of chess playing programs over the years. So it really tickles me how when then world champion Gary Kasparov lost to Deep Blue in a match back in 1997, many folks predicted that chess as a human past time would die. over a decade later, the situation is even worse for the humans: the best GM's can not hope to defeat the best programs, even at material odds. Yet the game is more popular than before. Part of the reason is online play thanks to the Internet. Another reason is that these strong chess engines make for primitive coaches. So the future of chess is safe for now.

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Software Development Software Development

Architectural Anxiety and the Waterfall Approach

Dietrich Kappe, Monday, February 8, 2010 @ 4:50 am

an unwitting victim...bwahahhahahaa
Creative Commons License photo credit: bark

We've discussed the benefits of Agile development before and that the iterative approach to building the architecture -- where you explore architectural issues (very few apps are completely new and unknown) a little bit through each iteration -- is an effective method for arriving at a good application architecture. What is less obvious is the psychological benefit to working in this way.

It's frankly been a while since I've participated in a large waterfall project directly (one benefit of working for a firm that does agile software product development), but I regularly talk with folks who are still in the corporate trenches doing things the old fashioned way. One thing that hasn't changed is the BIG ARCHITECTURE wrestling match up front. Management wants to know the architecture, the guys with "architect" in their job titles want to know the architecture (so they can criticize, natch), the project manager(s) want to know the architecture. How will we scale? How will we ensure security? More useless brainpower is spent on this ultimately fruitless task -- solving problems that end up being no problem at all -- than almost any other activity in the project.

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Software Development Software Development

Flashback: The iPhone and the Early Days of the Web

Dietrich Kappe, Friday, February 5, 2010 @ 3:19 pm

269/365 - why even have that deal?
Creative Commons License photo credit: B Rosen

I remember my first real grownup and serious web project outside of the university environment. It was 1994 and SSL was a novelty. People were making insane predictions that one day up to $600 million (think Dr. Evil) worth of consumer goods would be sold on the web worldwide. In 2007, just Canadian B2C sales were US$12.9 Billion.

Some folks, especially startups and smaller companies, saw the web as an opportunity to shake up the established order and establish a new sales channel or an entirely new business model. They invested what they could in building the first of what became known as e-commerce sites. Among established players, and some more conservative smaller players, there was initial hostility toward the new medium. When in 1994 I proposed to Ameritech (now part of SBC/AT&T) that they bring their lucrative print yellowpages online, I was run out of Hoffman Estates on a rail.

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Software Development Software Development

To the Moon: an iPhone with Wheels

Dietrich Kappe, Friday, February 5, 2010 @ 2:42 pm

A friend of mine from college is a physics professor who does a lot of stuff with the space station and the new Google Lunar X Prize, that awards up to $30 million for the first non-governmental organization to land a robot on the moon. He likes to get his students involved and has a gift for expressing things in terms they can immediately grasp. "The robot," he tells them, "can be small. Think of an iPhone with wheels."

When something has penetrated the collective consciousness the way the iPhone has, it changes the way we look at what is possible.

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Software Development Software Development

A Slight Correction to using PureMVC with Vaadin

Dietrich Kappe, Monday, February 1, 2010 @ 2:32 pm

A while back I looked at the Vaadin Plugin and tried to make it work with the Multiton PureMVC. Back then I proposed the following code:

 
public static ApplicationFacade getInstance() {
   if (instance == null) {
     // nuke the multiton so we can do the grails recompile
     if (ApplicationFacade.hasCore(CORE)) {
       ApplicationFacade.removeCore(CORE);
     }
     instance = new ApplicationFacade(CORE);
   }
   return instance;
 }
 

A little more noodling and you'll see that doesn't work. In a multi-session environment, each user will need his own core. Furthermore, inactive cores should be harvested, otherwise we will have a memory leak.
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User Driven Product Development

Dietrich Kappe, Monday, January 25, 2010 @ 8:02 pm

1958 Edsel Villager
Creative Commons License photo credit: Hugo90

This morning I sat through two pitches by two startups looking for funding. I won't get into the details, but they both had clever ideas at their root. But while one company was attractive and poised for success, the other was mediocre and not getting much traction. Why was that? They both had clever ideas, no?

Over the years I've looked at a lot of business plans for Venture Funds. The first lesson that I learned was that cool ideas didn't equal successful companies. While I would get all hot and bothered by a particularly elegant software solution, the VC's I was consulting to preferred the plans that understood the market and the customers in it (and had a kick ass management team, natch).
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Agile Product Management: The Concept Phase

Dietrich Kappe, Friday, January 15, 2010 @ 5:49 am

Scientist conducting an experiment
Creative Commons License photo credit: NIOSH

Academic research is incredibly inefficient when it comes to producing products and services. Grad students, post-docs and professors work on "problems" that some collection of graybeards has deemed "interesting." Their "solutions" -- sometimes successful, sometimes not -- are published as research and then, occasionally, if the stars align, is turned into a product or service through the application of venture capital via a startup.

The only thing less efficient in producing innovative products and service is the corporate R&D department. In most places you have a phase-gate process (waterfall under a different name) of conceptualization, feasibility testing, definition/specification, development and launch. They are typically bloated, bureaucratic monstrosities with huge documentation requirements and endless committee meetings that do more to stifle innovation than promote it.

There is a way, however, of applying Agile principles to the concept phase, and it relies on two of the basic tennets of Agile: failing fast and self organizing teams.

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Software Development Software Development

Prediction: The Teens will be the Decade of Mobile

Dietrich Kappe, Monday, January 11, 2010 @ 5:31 am

Abacus, Filofax, wrong result
Creative Commons License photo credit: matsuyuki

I've made my fair share of predictions, and this may seem to be a layup, but I think it's a prediction worth making anyway: mobile devices and applications will transform business and every day life in the next decade.

Why does this seem like such a layup? Well, look at the iPhone and the ecosystem of applications and companies springing up around it. Android and Blackberry are trying to jump in on the business and everybody and their brother is cooking up a connected mobile device. And yes, that's obvious. Mobile devices are going to increase in importance in 2010 and if you don't already have an iPhone app cooking to complement your other online channels, you're behind the times.

But if you're just thinking that more iPhone applications are going to be the end of it, you're in for a rude awakening. Businesses have just started consolidating after the disruptive years of the 90's and aught's, with the transformative effects of the web largely digested by the marketplace (the newspaper industry is still thrashing but will soon succumb). A new disruptive decade is dawning that may see the passing or fundamental transformation of industries as varied as telecom, credit card and broadcast television/cable. Prepare to take your business through a roller coaster ride every bit as challenging as the web revolution. Continue reading »

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User Experience Design User Experience Design

The Dog Ate My Software: Agile is not Undisciplined

Dietrich Kappe, Monday, January 4, 2010 @ 5:00 am

Boombastic
Creative Commons License photo credit: LKaestner

Back in college I used to work at the main campus computer center. That was back in the days of time sharing Unix and mainframe computers, so it was a great way to get some extra CPU time for my various projects. Besides locking up at closing time (I loved to work the 10pm-3am shift), I had to change toner cartridges, support the brick macs, windows 3.1 machines, and the various Unix and Mainframe terminal users.

Over time, you learned to identify various user types. The vast majority of users had simple "hey, how do I do this" or "this ain't working" types of issues. Of the rest there were two main problem user types: the "helpless bunny" and the "walking crisis."

The Bunny displayed profound helplessness in order to get you to do their work for them. The first time I had a Bunny, I was caught unawares and spent the better part of my shift formatting their document in Wordperfect. With subsequent Bunnies, I used tough love and gave them manuals and man pages to read.

The Walking Crisis was typified by the grad student who waited until the last moment to add end notes to their masters dissertation, and dammit, if they were going to suffer, you were going to suffer. Their technique was to try to convince you that their problem was your problem, i.e. the fact that they couldn't do two months of work in five hours was a shortcoming of the software, and thus a support issue.

The more enthusiastic you were about helping users, the more susceptible you were of being dragged down by the Bunny and the Crisis.

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Software Development Software Development

Getting CloudTools to Work with Grails 1.1.1

Dietrich Kappe, Tuesday, December 22, 2009 @ 4:46 pm

Thunderhead
Creative Commons License photo credit: °Florian

Yes, Cloud Foundry has been acquired by Spring Source and seems to be morphing into a for-pay service, and there hasn't been a new build packaged on the Cloud Tools project page since January of 2009, but if you dig in the SVN repo, you see there's a bit of activity. Before I try building from source, I wanted to see how hard it would be to get 0.6 Grails plugin working with a Grails 1.1.1 app.

Well, harder than I thought. There's a real lack of documentation around cloudtools for one, and the radio silence on the project page over the last few months hasn't helped. Fortunately, Don over at AlterThought has put together a nice post that covers most of the pitfalls and problems with the CloudTools Grails Plugin. A few things they don't address and I thought I'd throw in here:

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Software Development Software Development

Data Visualization is About More than Just Pretty Pictures

Dietrich Kappe, Friday, December 18, 2009 @ 5:32 am

waalerToo often in software development projects, we're asked to provide what I would call thoughtless reports. By this I mean a collection of tables and charts that depict and enumerate standard relationships. There's nothing wrong with the reports themselves, mind you -- we know how to present relationships in graphical form. No, the problem is that no one has given much thought to the relationships that are being depicted.

You've probably heard about the finding that in children, shoe sizes and handwriting quality are highly correlated. It would be wrong to conclude, however, that one causes the other. In fact, as children mature, their shoe size increases, as does their cognitive ability and their motor skills. They are all dependent on age. Continue reading »

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Software Development Software Development

Innovation and Punctuated Equilibrium

Dietrich Kappe, Thursday, December 17, 2009 @ 5:16 am

In my last post about innovation I referred to Clayton Christensen and his concepts of sustaining versus disruptive innovation. It reminded me a little bit of the concept of punctuated equilibrium in evolution.

The idea is simple: suppose you have a bunch of monkeys working in an office. You have the executive monkeys who eat healthy meals and exercise at lunch time. Then you have the office drone monkeys who go outside into the rain and cold for smoke breaks and eat gyros and fries for breakfast. The executive monkeys have nice glossy coats, get the best mates and have nice condos in desirable parts of town. The drone monkeys...not so much.

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