jruby: what, why, howdo it now! - oraclejava technology implementation of ruby language...

JRuby: What, Why, How...Do it Now!

Thomas E Enebo, JRuby Core DeveloperCharles Oliver Nutter, JRuby Core DeveloperTS-5416

2008 JavaOneSM Conference | java.sun.com/javaone | 2

Learn how awesome JRuby isLearn how much nicer Java™ technology-based APIs can beGet a taste for NetBeans™ Ruby and RailsAsk those burning questions you have


The JRuby Guys

Charles Oliver Nutter and Thomas EneboLongtime Java code developers (10+ yrs each)Engineers at Sun Microsystems for 1 yrFull-time JRuby developersAlso working on Java Virtual Machine (JVM) dynlang supportWide range of past experience• C, C++, C#, Perl, Python, Delphi, Lisp, Scheme• Java Platform, Enterprise Edition (Java EE) and Java Platform,

Micro Edition (Java ME), JINI™ (JINI), WS technologies


What is Ruby?Dynamically-typed pure object-oriented programming languageFocus on simplicity, productivity, and “fun”InterpretedOpen source, written in CImplementation is the SpecificationCreated 1993 by Yukihiro “Matz” Matsumoto“More powerful than Perl and more OO than Python”Very active community, wide range of apps


Ruby Quick Tour: Objects EverywherePure Object-Oriented LanguageLook mom...No primitives

7.class => Fixnum“hello”.length => 53.times { |i| puts “#{i}: No place like home” } => 1: No place like home 2: No place like home 3: No place like home


Ruby Quick Tour: Sweet SugarSyntactical sugar• Strings: “foo”• Arrays: ['one', 1, Ein.new]• Associative Arrays: {'a' => 3, 'b' => 4}• Regular Expressions: /^foo.*bar/


Ruby Quick Tour: Dynamic TypingDynamically-Typed Language (Duck-Typing)• “If it quacks like a duck and waddles like a duck then ...”

def make_it_waddle(waddler) waddler.waddleend

make_it_waddle(Duck.new) make_it_waddle(Penguin.new)make_it_waddle(Octopus.new)


Ruby Quick Tour: Classes and ModulesRuby classes are like Java classesRuby modules “mixin” behavior

module ShapeStuff def diameter return 2 * @radius endend

class Circle include ShapeStuff ...endCircle.new(4).diameter => 8


Ruby Quick Tour: BlocksAnonymous methods you can pass around and invoke• Add block to be invoked on end of method call• Removes repetitive code

• list.each { |element| ... do something ...}• Internalizes transactional code

• File.open(fname) {|file| line = file.gets ...}• Makes nice APIs


Ruby Quick Tour: MetaprogrammingOpen Classes• Dynamically generate class/module• Modify existing class/module

• Add, remove, alias, or replace methods• include a module• Add or remove class or instance variables

Special handler methods• method_missing• const_missing


JRubyJava technology implementation of Ruby language• “It's just Ruby!”

Started in 2002, open source, many contributors• Ola Bini, Marcin Mielzinsky, Nick Sieger, Bill Dortch, Vladimir

Sizikov, MenTaLguYAiming for compatibility with current Ruby version• Ruby 1.8.6 patchlevel 111 (114 was just released)

Improvements on Ruby• Native threading, better performance

Plays nice with Java technology• Call to Ruby from Java technology via JSR223, BSF, Spring• Use Java classes from Ruby (e.g. Script Java)


Interactive Ruby


What are People Doing with JRuby?Swing GUI development• Makes Swing much nicer to use, easier to handle

Tooling for IDEs• JRuby's parser enables NetBeans, Eclipse communities

Graphics• Ruby + graphics = cool demos

JRuby on Rails• Better deployment options, better performance


Swing GUI DevelopmentSwing API is very large, complex• Ruby magic simplifies most of the tricky bits

Java language is very verbose• Ruby makes Swing actually fun

No consistent cross-platform GUI library for Ruby• Swing works everywhere Java technology does (everywhere)

No fire-and-forget execution• No dependencies: any script works on any JRuby install


Swing in Ruby


Swing OptionsCheri - http://cheri.rubyforge.org/• Builder-like DSL syntax

Profligacy - http://ihate.rubyforge.org/profligacy/• Rubified layout expression language• Trivial event binding without listeners

MonkeyBars - http://monkeybars.rubyforge.org/• Leverage GUI builders• MVC structure

http://cheri.rubyforge.org/

http://ihate.rubyforge.org/profligacy/

http://monkeybars.rubyforge.org/


Cheriinclude Cheri::Swing

frame = swing.frame("Swing builders!") { |form| size 300, 300 box_layout form, :Y_AXIS content_pane { background :WHITE }

button("Event binding is nice") { |btn| on_click { btn.text = "You clicked me!" } }}

frame.visible = true


Profligacyclass ProfligacyDemo import javax.swing.* include Profligacy def initialize layout = "[<translate][*input][>result]" @ui = Swing::LEL.new(JFrame, layout) {|cmps, ints| cmps.translate = JButton.new("Translate") cmps.input = JtextField.new; cmps.result = JLabel.new

translator = proc {|id, evt| original = @ui.input.text translation = MyTranslator.translate(original) @ui.result.text = translation }

ints.translate = {:action => translator}...


Monkeybarsclass RssController < Monkeybars::Controller set_view "RssView" set_model "RssModel" close_action :exit add_listener :type => :mouse, :components => ["goButton", "articleList"] def go_button_mouse_released(view_state, event) model.feed_url = view_state.feed_url content = Kernel.open(model.feed_url).read @rss = RSS::Parser.parse(content, false) model.articles = @rss.items.map {|art| art.title} update_view ... ...


JRuby Enables ToolingJRuby's parser used by most Ruby IDEs• NetBeans Ruby Support• Eclipse RDT/RadRails/Aptana, DLTK, 3rd Rail• IntelliJ (not parser, but other areas)• Jedit

NetBeans community is the best right now


NetBeans Project Teaser


NetBeans Ruby TalksLAB-8400: Developing (J)Ruby on Rails Applications with the NetBeans™ IDE• Tuesday, 3:20PM-5:20PM

TS-5249: The NetBeans™ Ruby IDE: You Thought Rails Development Was Fun Before• Wednesday, 2:50PM-3:50PM


Pretty Graphics!“Processing is an open source programming language and environment for people who want to program images, animation, and interactions.”• Basically a cool Java library for 2D graphics

Ruby-Processing wraps Processing with JRuby• Cool, rubified 2D graphics environment for you• Eye-candy demos for us• Thanks to Jeremy Ashkenas for putting these together


Processing: Pretty Graphics


Introducing Ruby on Rails

A Full-stack MVC web development frameworkOpen Source (MIT), Many ContributorsWritten in RubySingle-Threaded designFirst released in 2004 by David Heinemeier HanssonRuby and Rails book sales are outselling Perl book salesShipping with “Leopard”


Ruby on Rails Precepts

Convention over Configuration• Why punish the common cases?• Encourages standard practices• Everything simpler and smaller

Don't Repeat Yourself (DRY)• Framework written around minimizing repetition• Repetitive code harmful to adaptability

Agile Development Environment• No recompile, deploy, restart cycles• Simple tools to generate code quickly• Testing built into framework


Why JRuby on Rails

Greatly simplified application development• “Less Rails code than Java application configuration”

Create applications quicklyDeployment to Java application servers (GlassFish)Easy Integration with existing Java TechnologyBetter performance, scaling


Rails Quick Tour: Components

ActiveRecord• Data-driven ORM

ActionPack• View and controller support

ActiveResource• RESTful exposure of resources

ActionMailer• Email

ActiveSupport• Unicode, json, miscellaneous helpers


Ruby on Rails Demo


Production JRuby on Rails

Oracle's Mix – digg-like social customer site• mix.oracle.com

Sun's MediaCast – file distribution portal• mediacast.sun.com

ThoughtWorks' Mingle – collaborative project mgmt• mingle.thoughtworks.com

Sonar – code/project analysis tool• sonar.hortis.ch

More on the way!


JRuby on Rails TalksTS-4806: JRuby on Rails: Web Development Evolved• Wednesday, 1:30PM-2:30PM

TS-6490: JRuby on Rails Deployment: What They Didn’t Tell You• Thursday, 10:50AM-11:50AM

BOF-5111: Scripting in GlassFish™ Project• Tuesday, 8:30PM-9:20PM

LAB-8400: Developing (J)Ruby on Rails Applications with the NetBeans™ IDE• Tuesday, 3:20PM-5:20PM

TS-5249: The NetBeans™ Ruby IDE: You Thought Rails Development Was Fun Before• Wednesday, 2:50PM-3:50PM


Other JRuby and Ruby-related TalksPAN-5345: The Script Bowl: A Rapid-Fire Comparison of Scripting Languages• Wednesday, 9:30AM-10:30AM

BOF-4807: JRuby at ThoughtWorks• Wednesday, 7:30PM-8:30PM

TS-4868: From Java™ Technology to Ruby...and Back• Thursday, 4:10PM-5:10PM

BOF-6554: PHP, Ruby and friends - going mobile• Thursday, 8:30PM-9:20PM

TS-6050: Comparing JRuby and Groovy• Wednesday, 1:30PM-2:30PM• Friday, 1:30PM-2:30PM


Summary

JRuby gives Java technology access to the Ruby language• Powerful, terse, and a whole lot of fun!

JRuby gives Java developers access to Ruby on Rails• The way web development should be• Driving force behind the “new way” in web frameworks

Many People are using JRuby today• Production ready• Fast• ...and still moving forward!


Thomas E Enebo, JRuby Core DeveloperCharles Oliver Nutter, JRuby Core Developer

TS-5416

jruby: what, why, howdo it now! - oraclejava technology implementation of ruby language...

Documents