JRuby: The power of Java
and Ruby
- by Uday Bhaskar
Sr., Java Programmer
Olive Technology
uday@olivetech.com
http://udaiibhaskar.blogspot.com

JRuby: The power of Java
and Ruby
Agenda
Introduction to Ruby
What is JRuby
JRuby on Rails
JRuby on Netbeans
Where To Go

JRuby: The power of Java
and Ruby
Introduction to Ruby
• Created by Yukihiro “Matz” Matsumoto
>Started around 1993, about the same time as Java
• What is a scripting language?
>No compilation unit
puts “Hello world”
>Specialized syntax
subject.gsub(/before/, \"after\")
>Maybe dynamic typing /duck typing
• Design to put the “fun” back into programming

JRuby: The power of Java
and Ruby
A Typical Ruby Class
class Person
attr_accessor :fname, :lname
def initialize(fname, lname)
@fname = fname
@lname = lname
end
def to_s
@lname + \", \" + @fname
end
end

JRuby: The power of Java
and Ruby
What is Ruby on Rails
• Main web framework for Ruby
• Scaffolding
• Metaprogramming
• Convention over configuration
• Web development that doesn’t hurt
• High productivity
>Less code to write
>No deployment
>Easy to learn

JRuby: The power of Java
and Ruby
Comparison of Rails and Struts Stack
• Tomcat servlet container
• Struts Web application framework
• Hibernate persistence framework

JRuby: The power of Java
and Ruby
Ruby/Java
• Ruby language is different from Java
• Ruby platform is different from Java
• How can Java developers benefit?

JRuby: The power of Java
and Ruby
What is JRuby?
• Implementation of Ruby written in Java
• Compatible with Ruby 1.8.6 http://jruby.codehaus.org/
• Enables use of Java code in Ruby
• Easier deployment
• More libraries
• More platforms, OpenSource
• “Itʼs just Ruby”

JRuby: The power of Java
and Ruby
JRuby Demo
Java:
VoiceManager vm = VoiceManager.getInstance();
Voice voice = vm.getVoice(\"kevin16\");
voice.allocate();
voice.speak(jTextArea1.getText());
voice.deallocate();
Ruby:
require 'java'
vm = com.sun.speech.freetts.VoiceManager.getInstance()
voice = vm.getVoice(\"kevin16\")
voice.allocate()
voice.speak(\"Calling Java code from Ruby\")
voice.deallocate()

JRuby: The power of Java
and Ruby
JRuby/Ruby on Rails Demo
I am using “Netbeans IDE” for
this Demo

JRuby: The power of Java
and Ruby
Questions
“Good Question!” means I don’t have an answer :-)

JRuby: The power of Java
and Ruby
Where to go for Ruby information
• Online material:
• http://jruby.codehaus.org/
• http://rubyonrails.org/
• Rails screencast(s)
• Planet Ruby on Rails

Thank You
- by Uday Bhaskar
Sr., Java Programmer
Olive InfoServices
uday@olivetech.com
http://udaiibhaskar.blogspot.com