billpratt.net » Software Development

Object Oriented Analysis And Design With Applications

Bill — Mon, 08 Dec 2008 19:02:22 +0000

I started Object Oriented Analysis and Design a few months ago and have been reading it in what spare time I have. I sought out a book to help further my skills in software design practices, especially in object modeling and overall object oriented software design. After reading almost two-thirds of this book, I have learned a lot. The book is very thorough, very technical, but very well written. Reading this book twice is a must as there is not intro to some of the terminology used throughout. It is not hard to follow by any means, however, a second reading will undoubtedly result in a more thorough understanding of the concepts and how to best apply them. A detailed journey into the world of UML is a bonus, and as some have called it, a “mini-book” within this book. If you are unfamiliar with UML, or just want to learn it from one of it’s creators, these chapters will be a tremendous asset to you. Grady Booch is know as the father of the object model and is an expert in object modeling, patterns, and UML. He was the developer of the UML. I have not made it to the sample applications included in the book so watch for an update once I finish the book.

Firefox, Localhost, and Work Offline

Bill — Fri, 05 Dec 2008 23:14:09 +0000

I have a laptop configured as a trade show demo that uses html & cgi files copied from a live web site along with the accompanying mysql data copied to a local mysql instance and a few host entries changing public resolving host names to point to localhost. This all worked well until I upgraded to Firefox 3 (laptop runs Fedora 10) and then the “Work Offline” issue started. By default, if Firefox does not detect an active network link, it forces the browser into “Work Offline” mode. It’s easy to work around, you simply uncheck a setting in the File menu (File => Work Offline.) But, this is ugly if you launch Firefox in front of clients who want to see the demo as the page Firefox displays looks very similar to an error. I found a fantastic solution from someone at Yellosoft.us that had the same problem. You can install their “Always Online” plugin which prevents Firefox from entering offline mode (who uses offline mode anyway?). I hope this helps someone and props to those who authored this plugin at Yellosoft.us.

Expected things_controller.rb to define ThingsController

Bill — Mon, 10 Mar 2008 19:02:06 +0000

Well, I had fun with this rather obscure error today. The basics are simple, for some reason, app/controllers/things_controller.rb could not be loaded or did not supply the expected class ThingsController. One common cause of this is that the helper for this controller is mistakenly named in singular form instead of plural. In the case of app/controllers/things_controller.rb, make sure app/helpers/things_helper.rb is not named thing_helper.rb and that the module it is supplying is named ThingsHelper and not ThingHelper. It is ok if the helper does not exist at all. This error is sometimes even more difficult to debug in the case of a misnamed helper because it can appear to be intermittent. The problem will only occur when a method defined in the helper is called due to lazy instantiation.

I hope this helps someone. As always, comments are welcome.

Design Patterns in Ruby

Bill — Sat, 23 Feb 2008 19:55:26 +0000

If you are a Ruby nut like I am or you are just beginning in the language, I highly recommend Russ Olsen’s Design Patterns in Ruby. The book covers many of the original “Gang of Four” patterns from the classic book Design Patterns but it applies all of the Ruby magic that is inherent in the language. For those new to Ruby, this is not really a starters book, but it does have a simple introduction to the language that would suffice for those with development experience in other languages, especially object oriented languages. The examples in the book are well thought out and include enough detail to allow the reader to understand the pattern in full, without going too far which could obscure the point of the example. Congratulation Russ, this is a fantastic book.