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Showing posts from October, 2011

Don't expose class internals

I'm going to disagree a bit with Robert Martin, the author of Clean Code. In his G14 "Feature Envy" smell he uses the example of an method on an HourlyPayCalculator class that takes an HourlyEmployee argument and then uses its properties to do its job. That makes the method "envy" the HourlyEmployee class - the method "wishes it was inside the HourlyEmployee class". So far, so good. Unfortunately, Robert continues with a counter-example to the feature envy smell; he uses the following example (Java code): public class HourlyEmployeeReport { private HourlyEmployee employee; public HourlyEmployeeReport(HourlyEmployee e) { this.employee = e; } String reportHours() { return String.format("Name: %s\tHours: %d.%1d\n", employee.getName(), employee.getTenthsWorked()/10, employee.getTenthsWorked()%10); } } Robert says: "Clearly, the reportHours method envies the HourlyEmployee class. On t…

The Awakening

The source of their Powers was never discovered; what nobody had doubted, however, was that there was a will behind it. Both the fact that there were exactly nine of them – one for each billion people – and the fact that each of them gained their powers on January 1st, 2050, at exactly midnight local time, made coincidence a too unlikely explanation. Once it found out about their existence, the world called them superheroes; but amongst themselves they would use the name Champions. The people would not discover the existence of the Champions for more than a year, though, because at the same time they had gained their powers, the Universe had started responding to spells. Some would call them wishes, or prayers; whatever the name, people's intentions were starting to directly affect the real world. Like many religions had insisted, it would only happen if the person making the wish genuinely believed in it; unlike what those religions had taught, the effect of the wish appeared t…

TDD by example - first book

This is an alpha version of a TDD booklet I wrote. As I said earlier, I plan on writing several of these. TDD by example - Evaluating an expression [pdf] It's a hands-on book; if you don't plan to follow it by writing code, it might not be of any help. The intended target are people who have done no TDD at all, or who tried it and couldn't make it work. If you have experience doing TDD, this book will probably look childish. Feedback will be strongly appreciated. Positive if at all possible, but even "it sucks" is better than nothing :) The book is also available from Amazon for $4.99 for Kindle (if you're in the US or Canada; I know Amazon changes the price in other countries) or $14.99 in paperback.