Month: June 2009

View Larger MapRecently, I tweeted about reading Steven Johnson’s book, The Ghost Map.  It’s a book that ties in with my PNSQC paper in a very odd way which I’ll write about later.  What I noticed as I was reading, is that the way I read has changed.  The Ghost Map is about a cholera outbreak in London during late August/early September of 1854.

Even though I’m only 1/5 through the book, I’ve already looked up all of the places on Google street view.  This is a new and an old thing for me.  Whenever I’ve read books about a certain location, the next step, for me has always been to find a map of the location and take a good look.  This time, not only can I see the layout of the streets, but I can see what they look like “on the ground.”  Johnson writes about how crowded the streets are and about the dense population of the area.  If you look at streetview, this is immediately noticeable.

Although my copy of this is book is a dead-tree copy, I have to wonder how my experience would change if I had an e-Reader.  With the current paradigm shift taking place from dead-tree books to e-readers, I expect that books themselves will change and will allow the reader different ways to explore their content.  This, in turn, will create different expectations from those who are reading.  I won’t be going from my dead-tree book to my computer to look at the Soho area of London.

Some of you may have used Zemanta for blogging.  Zemanta sits next to the window where I write text in my blog and makes suggestions for pictures and links while I type.   Although, at this point in time, I use Zemanta for writing, I can see a Zemanta like integration for reading as well.  One of the first chapters in The Ghost Map describes clergyman Henry Whitehead making his rounds through the neighborhood.  I’d love to see a map next to the text that I am reading which shows the route he is taking or pictures of some of the places he is visiting.

Language is its own art form.  You can’t just replace a book with a bunch of pictures and links, but there is more than one way to explore writing.  The best writers, I believe, will find ways to integrate the language of their writing with the exploratory journeys their readers take.

Have you noticed differences in the way you read?  How do you think reading will change as we move from paper to e-readers?  If so, I’m very interested in hearing about it.

This pattern is also known as publish/subscribe. It’s mainly used for keeping objects updated. The object sending out updates is called the “Subject” and the objects receiving updates are called “Observers.”

As a one-to-many example, think of Little Red Riding Hood (LRRH…she recently converted to Scientology. It was on TMZ). She’s setting up Grandma’s RSS feed for the very first time.
Grandma only has 1 feed, from her favorite televangelist, Mozelle Patterson. Grandma only has one feed because after LRRH set it up for her, she’s probably not going to go looking for more.

Mozelle Patterson is a televangelist here in the ATL who has a show on a local channel every Saturday that can, at times, be more amusing than SNL. Let’s say Mozelle Patterson has an RSS feed. Her feed is the subject. All the grandmas who have had someone set up their RSS feed, get the Mozelle Patterson feed. All of the grandmas, including LRRH’s, are the observers.

**subject**

Mozelle

|

|

v

** observer**
-Little Red Riding Hood’s Grandma

**observer**

-Sleeping Beauty’s Grandma

**observer**
-Anansi’s Grandma

Notice that, previously, I said that this is the 1 to many example. Why? Because the next time LRRH visits, she notices that Grandma hasn’t added anymore feeds, but she knows that Mozelle has a special feed specifically for the Gospel music featured on the show, and she adds that to Grandma’s reader. Now, Grandma has 2 different types of feeds from the same place. That’s many to many.

Here’s a class diagram of the 1-to-many example. Note: this is my example, and it’s not guaranteed to be perfect, so don’t take it as “gospel.”

Push/Pull
There are two types of Subject/Observer relationshiop. In the “Push” relationship, the Subject will send the observer everything it needs on notify. For example, If Mozelle’s rss feed contained all of the highlight from the show with pictures, etc., this would be a push. If the feed only contained the title of the show, and Grandma had to click through to view the show highlights, then it would be a pull relationship.

Loose Coupling
This pattern is a great example of loose coupling, because the subject doesn’t know that much about its observers. The observers operate freely and independatly of their updates from the Subject.

I’m taking Design Patterns this Summer.  At this point, I’ve coded enough Java to be able to say I can code Java.  However, I also know that my code typically is not, ahem, polished.  Take for example, this past week.  We’ve been going over publish/subscribe.  Some may call it the “Observer” pattern.  I call it the distributed message queue system I made for distributed systems class a year ago.  Hindsight is always 20/20, right?

Design Patterns is all about avoiding DRY.  This is something that I’m going through even with the Automated Test Framework that I’m writing at work.  It’s all Unix shell scripts.  Since shell scripting was created when programming pretty much meant that you were programming the OS, the syntax itself wasn’t particularly intented to be OO (insert e-vil grin here)…but that doesn’t mean that it can’t be.  At this point, I’ve got scripts everywhere, and they are settling into a pattern.  I chose test patterns and test harness patterns as my research topic for the class. I’m waiting to see if, in the course of my research I find myself looking in the test patterns mirror at my own automated test framework.

In the meantime, I will be making a few posts this Summer about Design Patterns.  I’ll post my research assignment too.  I’m so happy that my teacher is using Head First Design Patterns.  I know that THE Design Patterns book is Design Patterns: Elements of Reusable Object-Oriented Software, typically known as the “The Gang Of Four” book, but the information in Head First Books is always so much easier to remember.  They remind me of The Best Calculus Teacher Ever, Dr. Kathleen Hall who was considered somewhat unorthodox in using colors, YES! colors for describing calculus concepts on the black board.  Every time I read a Head First book or find myself taking the derivative of something, I think fondly on Dr. Hall and her classes.