In case you don’t know how to define class methods in Ruby, there are several ways to do it. But the one I prefer is,

class Book
  def self.title
    true
  end

  def title
    true
  end
end

self refers to the object depends on its context. self.title in the above example will be invoked by the (current) object, Book. While title will be invoked by the object, Book.new. Therefore, to determine the value of self, you need to think around where the self resides. I highly recommended you to read the smart summary by Paul Barry. And then you should get the idea what the following code is trying to do

class SelfStudy
  attr_accessor :name

  def self
    @name
  end

  def self.name
    @name
  end

  def self.name=(name)
    @name = name
  end

  def self.default_name
    self.name = "ClassName"
  end

  def default_name
    self.name = "InstanceName"
  end
end

puts SelfStudy.name
#=> nil
puts SelfStudy.default_name
#=> ClassName

me = SelfStudy.new
puts me.name
#=> nil
puts me.default_name
#=> InstanceName

puts SelfStudy.name 
#=> ClassName
puts SelfStudy.default_name
#=> ClassName

Please note the I just want to play up with self in the above example. So instead of defining @name in self method. As you should already know, you may simply replace it with

@name = nil

And you’d get the same output.

validates_presence_of [:fname, :lname, :email, :update_reason]

There’s nothing wrong with that except :update_reason. Because :update_reason could actually be empty on creation since its purpose is for modification log only. Thanks to beautiful Rails validation API, the above validation could be fixed as follow:

validates_presence_of [:fname, :lname, :email]
validates_presence_of :update_reason, :on => :update

In consequence, :update_reason will be ignore on create but checking for emptiness on update. Nice and effortless, isn’t it!?

The first idea about this thing would be about character set. Especially, when the source of data came from Access And well, I was right. The character set was TIS-620 and our current MySQL database is (definitely) using UTF-8. The solution is simple. Just use iconv to convert between character sets like the following:

require ‘iconv’

row = Iconv.new(”UTF-8″,”TIS-620”).iconv(row)

And then you should be good to go now!

For Ubuntu users, they use the same command with Windows user but save as file instead of clipboard. For Mac users, they have richer options. Either save into the clipboard or save as file. See the table here.

In software development, there’s a good chance, you want to create a screenshot only in the preferred area. Mac does provide this option with Command+Shift+4 but not in Ubuntu (and Windows). Fortunately, there is project Desktop Data Manager, which provides features like creating a region screenshot similar to Mac. So you don’t have to edit it with GIMP as the second step.

Follow the article here for the download instruction and tutorial. Hope this will be helpful

Moreover, the ongoing project that I’m involved seems to have high demands on richness UI (look at their samples). And ExtJS does cover majority of UI controls and has a well designed for extensibility. Besides, the document is good and the community is very active. Another nice thing of ExtJS is it allows you to build the library based on what you need which helps reducing the library size with less effort.

If you’re working with Rails, you might want to check an example here. Although Rails seems to get along fine with ExtJS but I think there could be a less effort way to work between them. And there is a couple of plugins that might be useful. I’ll report back soon after I really checked them out

I spent a little time working with it since I ever used it before. Besides, the usage of this plugin is very simple and straightforward, hail to Rick Olson. Consult the post by Juixe here if you want some examples.

However the problem happened when I run the migration file. Rails alerted me that there’s no method named create_versioned_table for Quotation (my model here). I made sure that I already put acts_as_versioned on the Quotation model (which make Quotation now has the abilities of Acts As Versioned) but the problem still exist.

I spent a big while tried to find what caused this problem. I talked with a junior colleague who said he found a similar problem like this before, and fixed it by renaming the migration file. He didn’t know what caused the problem and why it’s fixed that way. So I didn’t buy it at the first because at that moment, I still have no idea what is the relation between the migration’s filename and this problem. Until I noticed that a migration file was named as 005_quotation.rb with class named Quotation

OK, I got it now!

The problem was that when I called Quotation.create_versioned_table in the migration file. The Quotation here is not Quotation model as I intended but it’s migration class named Quotation. Thus it doesn’t know create_versioned_table method. So fix it by renaming the migration class (and filename) to what is should be, CreateQuotation (005_create_quotation.rb).

Problem solved , I’m happy now.

However, it seems they’ve few problems of using it at the moment. Some people are afraid to face the conflicts. The development line is made solely on trunk although some modifications cause major effects to everyone. In the end, I decided to bring up another talk for subversion as a revisit. At least to make sure everyone is on the same page. The slide is as follow.

If I manage to have some free time I might record an audiocast for this one.
Or maybe it’s time for Git

In trade to get the snappier OS, Quick Look, unnoticeably better Finder and Time Machine that I haven’t used.

• For Java 6 I’ve used SoyLatte (hail to Landon Fuller!
• For TextEdit, I went for vi or JEdit.
• For lacks of input source state of each window, I’ve tried to get used to with it!

However, the last problem was fine for me until I used Ubuntu during the day and Ubuntu does remember the state like every OS supposed to do! Fortunately, there is InputSwitcher which made by Satoshi Nakagawa (I love Japan!). The problem gone, and now I’m happy again

However, by the time pass by, I paid more attention to more technologies not limited to just Java related. One thing that I paid most attention is Ruby. Again, I felt awkward at the first time I tried to do things with it. But soon I started to understand the way it’s been designed and how to work with it in a proper way. I’m impressed. And that might be the reason that lead me to working with Ruby and Rails at the moment.

I have some unpublished posts during the time I worked with Java which is mostly about Swing. It was kept unpublished because most of them are not finished articles. I was a lazy person (and still be!). But I think it was very unfortunate for everyone and particularly myself, to not be able to capture and transfer knowledge I posessed. This is the main reason I’d like to start afresh at this blog. It would be mainly about but not limited to Ruby, Rails, Java and other related fields. Additionally, I decided to import a few posts from my original blog so it could be kept at a single place and would be more handy for you and myself.

Thanks

I didn’t plan to get back here on the summer because I would have a hard time to stand the heat. But eventually I’m here, in the middle of hot hot summer. The temperature is over the bar as I thought, however it’s not that bad. Things around here haven’t changed so much, and neither do I. Except that I feel more mature and really couldn’t wait to start the new beginning.