mobalean

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At mobalean we love to build innovative web services for Japan and the world. Our experience will help transform your ideas into successful online services.

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Mobalean is lead by Henri Servomaa, the original founder and mobile developer. At Mobalean we strive to develop services which are loved by our clients and users. By working in an agile manner, quickly adapting to changing requirements, we can deliver quickly and often.

Henri Servomaa

Henri

Hailing from Finland, Henri has a long history with computers and the internet. With a background in Electrical Engineering and Computer Science, he has worked in Japan as Software Developer and System Admin since 2001. In 2005, he joined a company to develop mobile sites for the Japanese market and has been involved in mobile ever since.

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Twitter
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github
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Contractors

Cleve

Cleve Lendon is a Canadian engineer who has been contracting for Mobalean. He came to Tokyo in 1994, and has lived here ever since. He has broad experience as a software developer, which includes development of mainframe software, Internet applications and mobile apps (Android and iOS). He is especially skilled at writing Java applications (vd. Simredo 4, Grafikilo 15). When not programming, Cleve enjoys improv acting and studying languages, such as Latin and Esperanto.

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Mobalean Alumni

Paul McMahon and Michael Reinsch were co-founders of Mobalean. They have moved to Doorkeeper KK, a company they established in 2013. Both are now actively developing the doorkeeper platform.

Web Development

Our strength is crafting web services for both Japanese and international markets. We bring our technical and cultural experience to help you adapt your ideas into successful products.

We develop with Ruby on Rails and use the best agile practices and tools, such as test driven development and continuous integration to achieve quality.

Japanese Mobile Consulting

We are the leading provider of technical expertise about the Japanese mobile web. Mobalean started when the smartphones were just appearing on the market. Our Keitai Web Technology Guide is a quick starting point for learning about the initial challenges of Japanese mobile development. Although the technology stacks have changed since the proliferation of iOS and Android, some of the idiosyncrasies remain. Most notably, the Japanese market is still very much dominated by the big three carriers: DoCoMo, au and Softbank. Developers can find more technical details in our Keitai-Dev Wiki.


Please contact us with your specific requirements.

Others

Originally developed here, Doorkeeper can now be found at doorkeeper inc.

Some of our clients

  • Reaktor Japan KK.

    Reaktor Japan, KK..

    http://www.reaktor.co.jp/
  • Ubiquitous Business Technology, Inc.

    Ubiquitous Business Technology, Inc.

    http://www.ubit.com/
  • PayPal Pte. Ltd.

    PayPal Pte. Ltd.

    http://www.paypal.com/
  • Robert Bosch Co., Ltd.

    Robert Bosch Co., Ltd.

    http://www.bosch.com/
  • GILT GROUPE K.K.

    GILT GROUPE K.K.

    http://www.gilt.jp/
  • Cerego Japan Inc.

    Cerego Japan Inc.

    http://www.cerego.com/
  • GMAP KK

    GMAP KK

    http://gmap.jp/
  • Mobikyo K.K.

    Mobikyo K.K.

    http://mobikyo.jp/
  • Native Creative Services

    Native Creative Services

    http://www.gonative.jp/
  • InnoviData GmbH

    InnoviData GmbH

    http://www.innovidata.de/
  • Sairis Group, KK

    Sairis Group, KK

    http://www.sairis.com/
  • Gerd Leonhard, MediaFuturist.com

    Gerd Leonhard, MediaFuturist.com

    http://www.mediafuturist.com/
  • Script Interactive

    Script Interactive

    http://www.script-interactive.com/

Send us a message

    

Send us an email

Email address: info@mobalean.com

Call us

If you prefer to call us, feel free to do so under +81 (0)70-6251-7245
For users of Skype, please call mobalean

Dynamic Methods vs. Method Missing

  

Posted by Paul McMahon on 2011-09-08

For a class I'm organizing on metaprograming in Ruby, we’re using Metaprograming Ruby as a textbook. In the chapter Tuesday: Methods, the book introduces two techniques for removing duplication: dynamically defining methods and using method_missing. It gives examples of applying both techniques to some sample code of which a simplified version is reproduced below:

# initial code
class Computer
  def initialize(data_source)
    @data_source = data_source
  end

  def mouse
    puts "Price: #{data_source.mouse_price}"
  end

  def keyboard
    puts "Price: #{data_source.mouse_price}"
  end

  def monitor
    puts "Price: #{data_source.mouse_price}"
  end
  
  #...
end

# dynamic methods
class Computer
  def initialize(data_source)
    @data_source.methods.grep(/^(.*)_price\$/) { Computer.define_component \$1 }
  end
  
  def self.define_component(name)
    define_method(name) do
      puts "Price: #{data_source.send("#{name}_price")
    end
  end
end

# method_missing
class Computer
  instance_methods.each do |m|
    undef_method m unless m.to_s =~ /^__|method_missing|respond_to?/
  end

  def method_missing(name, *args)
    super if !respond_to?(name)
    puts "Price: #{data_source.send("#{name}_price")
  end

  def respond_to?(method)
    @data_source.respond_to?("#{name}_price")
  end
end

However, the book doesn't discuss when you should use one technique versus another. Here’s my rule: only use method_missing when it is infeasible to use dynamic methods.

One good example of using method_missing is ActiveRecord's find_by method. With it, you can call a method like find_by_name_and_birthdate. While ActiveRecord could theoretically use the dynamic method technique, generating every possible method would be overkill, thus using method_missing makes sense.

One counter example can be found in an example in the Metaprograming Ruby book itself:

class Roulette
  def method_missing(name, *args)
    person = name.to_s.capitalize 
    super unless %w[Bob Frank Bill].include? person
    number = 0
    3.times do
      number = rand(10) + 1
      puts "#{number}..."
    end
    "#{person} got a #{number}"
  end
end

In this case, we have three methods we want Roulette to respond to: bob, frank, and bill. As we know these methods in advance, you should use the dynamic_method strategy:

class Roulette
  %w[bob frank bill].each do |name|
    define_method name do
      number = 0
      3.times do
        number = rand(10) + 1
        puts "#{number}..."
      end
      "#{name.to_s.capitalize} got a #{number}"
    end
  end
end

Now back to our initial example with Computer, which technique should we apply? Given that we can apply the dynamic methods technique, we should use it. Oh, and assuming we are always passed an instance of DataStore, I'd refactor it like so:

# dynamic methods
class Computer
  DataSource.methods.grep(/^(.*)_price\$/).each do |name|
    define_method(name) do
      puts "Price: #{data_source.send("#{name}_price")
    end
  end
end
  



Archive

2021-01-12   Upgrading Rails, 3.2 to 5.2
2016-12-05   Upgrading Ruby, 1.8 to 2.3
2016-02-16   Do you have entropy?
2015-11-09   Asset Pipeline for Clojure
2015-10-29   New logo for mobalean and other announcements
2013-03-03   Keeping your database in sync with your current branch
2013-02-24   Running Rails tests on a CI server
2013-01-31   Text Files as a CMS
2012-10-05   Truncating Text With CSS
2012-09-28   Mobalean becomes a Heroku partner
2012-05-08   Cleaning up your CSS with selectors
2012-03-15   請求書.jpのスタンドファーム社への譲渡について
2012-01-13   The Joy of Gems: Cooking up Rails Plugins
2011-09-08   Dynamic Methods vs. Method Missing
2011-09-02   Guessing a String's Encoding Under Ruby 1.9
2011-08-02   PDF generation and Heroku
2011-07-20   A Step Towards Internationalizing the Japanese Ruby Community
2011-07-14   Rubyを使っての英語学習
2011-06-29   Using the Asset Pipeline under Rails 3.1
2010-12-03   Updating a real world application to Rails 3
2010-11-19   Seamless Rails integration with jQuery Tools Dateinput
2010-11-12   Kara-mail for Japanese mobile sites
2010-10-14   Challenges faced creating a mobile site in Japan
2010-09-02   Announcing Tokyo Rubyist Meetup
2010-08-20   Keitai Web Technology Guide
2010-08-16   delayed_job (and other daemons) in a production environment
2010-07-04   Announcing Doorkeeper: Easy Event Ticketing and Check-in
2010-04-09   Enabling url parameter based sessions in Ruby on Rails
2010-02-15   Mobalean and Keitai-dev Wiki merge
2010-02-05   mobalean WURFL patch merged into core WURFL
2010-01-27   IMJ Mobile Releases Free Collection of Mobile Surveys
2009-12-04   KEITAIALL: Specs on all Japanese Mobiles
2009-11-19   Betrend releases report on mobile access in Japan
2009-11-16   XHTML support and Japanese Carriers
2009-06-10   mobalean releases Japanese WURFL patch, ruby libraries
2009-05-22   docomo to support JavaScript, external CSS, cookies, and more
2009-05-15   New docomo handsets to support cookies and send referrers?
2009-03-16   Japanese Mobile Support for Cake PHP
2009-03-05   mobalean to present at next Tokyo 2.0
2009-03-02   emobile wireless Internet access with Linux
2009-02-28   Hacking Ruby's default arguments
2009-02-25   docomo to launch SNS
2009-02-10   Ninjava Presentation
2009-02-10   Six weeks in
2009-02-06   Automatic Deployment via git
2009-02-01   Hosting git repositories
2009-01-30   mobalean Blog Live

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