JRuby on Rails

1
JRuby on Rails

• GAO ANG
• Sun Functional Campus Ambassador
• http//www.gaoang.com
• tomgaoang_at_gmail.com

1
2
Agenda
Introduction to Ruby
What is JRuby
JRuby on Rails
JRuby on Netbeans
Where To Go
3
What is Ruby?

• Created/lead by Matz
• Open Source interpreted scripting language, like
  Perl, Python, Tcl, etc.
• Focused on being very object oriented,
  expressive, and bringing joy to programming.

4
Ruby calling Java

• require javainclude_class javax.swing.JFrame
  include_class javax.swing.JButtonfrm
  JFrame.new(My frame)btn JButton.new(My
  button)frm.set_size(300, 300)frm.content_pane.
  add(btn)frm.show

5
Interactive ruby console irbirb

• This powerful tool can be used for trying out
  single line commands while you are getting used
  to Ruby, or to run whole programs.

6
Ruby in a nutshell RubyGems

• Ruby Gem http//docs.rubygems.org/
• Examples
• gem list
• gem install redcloth --version "gt 3.0.0"
• Using gems in your program
• require rubygems
• require some_gem

7
What is Ruby on Rails

• Web Framework that makes MVC-oriented web apps
  easy through a template engine, ORM
  (ActiveRecord) ,test driven development.
• Much less complicated than J2EE solutions, but
  perhaps more so than PHP or Perl in cgi-bin.
• Similar Web Framework
• Python (TurboGears, Django)
• Perl (Maypole)
• Groovy on Rails (Grails)
• Ruby(Merb)

8
Java and Rails
9
Rails Architecture

• Rails applications are implemented using the
  Model-View-Controller (MVC)
• Model - ActiveRecord
• View - ActionView
• Controller - ActionController

10
Comparison of Rails and J2EE stacks

• Tomcat servlet container
• Struts Web application framework
• Hibernate persistence framework

11
Database Migration (Bookmarks)

• db/migrate/001_create_bookmarks.rb
• class CreateBookmarks lt ActiveRecordMigration
• def self.up
• create_table bookmarks do t
• t.column url, string
• t.column title, string
• end
• end
• def self.down
• drop_table bookmarks
• end
• end

12
Running the Migration

• Rake is the general purpose build tool for rails,
  much like make, or ant. It has many functions,
  one of which is to control migrations.
• rake dbmigrate
• Now the table has been created
• Migration in Netbeans

13
What is JRuby
http//jruby.codehaus.org/

• 100 Java impl of Ruby
• Ruby on the JVM
• Pure interpreted, native threaded
• Born 2001, product of many developers
• Largely Ruby 1.8-compatible
• Slower than Ruby...for now

14
Why JRuby on Rails

• Java is pervasive
• Java libraries are exhaustive
• Many still believe Java is the everytool
• Java webapp developers are unhappy
• Rails webapp developers are happy

15
Advantage of JRuby on Rails

• JRuby on Rails mostly works right now
• JRuby will not be done until its fully working
• ActiveRecord-JDBC opens many doors
• Java EE is actually fun with Rails
• More Rails is more Rails...JRuby enables!

16
JRuby on Netbeans
17
Netbeans 6.1 Depot Demo
18
Where to go for Ruby information

• Online material
• http//www.ruby-doc.org/
• http//rubyonrails.org/
• Rails screencast(s)
• Planet Ruby on Rails

19
Netbeans 6 Resources

• Netbeans Product Site http//www.netbeans.org
• Download previews, current past releases of
  IDE, plugins
• Learning tutorials, technical articles, flash
  demos
• Community latest news, forums, events, mailing
  lists
• Netbeans Wiki http//wiki.netbeans.org/wiki/
• Open-source documentation site for Netbeans.
• Planet Netbeans http//www.planetnetbeans.org/
• Aggregate for all Netbeans-related blogs
• Netbeans TV http//www.netbeans.tv/
• Connecting the diverse and worldwide community of
  People, Projects and Technologies surrounding
  NetBeans.

20
Stay In Touch

• Check blog regularly
• http//blogs.sun.com/
• http//www.javapassion.com/
• http//blogs.sun.com/GaoAng/
• Join Java Open Source User Group
• BJUG http//www.bjug.org/
• BLUG http//www.beijinglug.org/
• You Can find lots of material on
• http//developers.sun.com/students/

21
Resources

• http//java.sun.com/
• Java 2 Platform, Standard Edition v1.4.1
• java, javac, jar, jre, etc.
• Online documentation and tutorials
• http//www.netbeans.org/
• Docs Support
• Netbeans Tutorials Training
• Get the latest version of Netbeans
• http//developers.sun.com.cn/
• The Source for Sun Developer Solutions
• http//www.sunacademic.com

22
THANK YOU

• Gao Ang
• Sun Functional Campus Ambassador
• http//www.gaoang.com
• tomgaoang_at_gmail.com

30