The document provides an overview of the Google Web Toolkit (GWT), detailing its inception, evolution, and features such as Java-to-JavaScript compilation, deferred binding, and support for AJAX applications. It highlights GWT's adoption by major Google products and the establishment of a steering committee to enhance its open-source development. The document also includes references to GWT resources, frameworks, and the benefits of using GWT for web application development.

1. GWT-Kickoff
Alberto Mancini - Francesca Tosi
alberto@jooink.com - francesca@jooink.com
Kickoff

2. Alberto
alberto@jooink.com
http://github.com/jooink
http://www.jooink.com
http://jooink.blogspot.com

3. Francesca
francesca@jooink.com
+FrancescaTosi
@francescatosi
http://github.com/jooink
http://www.jooink.com
http://jooink.blogspot.com

4. GDGFirenze
www.gdg-firenze.info
+GDG-Firenze

5. GWTcos’è Google Web Toolkit (GWT) is an open source Java software
development kit that makes writing AJAX applications like
Google Maps and Gmail easy for developers.
http://www.gwtproject.org/

6. GWTStats Official GWT Report by Vaadin
[2012] -
https://vaadin.com/gwt-report-2012-
portlet/download/1871870899/Future-of-GWT-Report-2012.
pdf
[2013] - (del 10/04/2014 → GWT in crescita)
https://vaadin.com/documents/10187/42fbbec4-51c8-426b-
8aa8-fe46129353a3

7. GWTStats
E’ uno fra i
framework più
utilizzati
http://zeroturnaround.com/rebellabs/the-curious-
coders-java-web-frameworks-comparison-spring-
mvc-grails-vaadin-gwt-wicket-play-struts-and-jsf/

8. GWTStats Come viene
principalmente
utilizzato

9. GWTStats Browser &
platform
support.

10. GWTStats GWT è
molto usato in Europa

11. GWTStats GWT
why i love it ;-)

12. GWTStats GWT
the dark side

13. rightfor?

14. GWTStats as of Q4/2012
● SDK downloaded over 1 million times
● 100,000+ Active Developers
● Deep Integration with Eclipse, IntelliJ, Spring STS/Roo
● Used by Google products such as AdWords, Flights,
Wallet
● Fun things: GwtQuake, Angry Birds for the Web
● GWT Today is a mature, high quality, code base.

15. ...notaFramework
Frameworks that may help
https://github.com/ArcBees/GWTP
model-view-presenter framework
http://www.jboss.org/errai
CDI, and JPA for GWT
http://www.tessell.org/
app framework (on gwt-pectin)

16. Ecosystem
Sencha’s GXT - http://www.sencha.com/products/gxt/
https://vaadin.com/gwt
http://code.google.com/p/smartgwt/

17. Why
Why?

18. FOSS
The GWT Steering committee was founded in 2012 to help
the GWT project become an even bigger success as an open
source project.
● Ray Cromwell, Google
● Artur Signell, Vaadin
● Colin Alworth, Sencha
● Mike Brock, RedHat
● Thomas Broyer
● Stephen Haberman, Bizo
● Daniel Kurka, Google
● Christian Goudreau, Arcbees
● Konstantin Solomatov, Jetbrains

19. Evolving&Mature
Rev. Improvements
2006 GWT 1.0
2007 GWT 1.3/GWT 1.4 First Open Source Release, OSX support / JUnit and ImageBundle
2008 GWT 1.5 Java 1.5 support, Overlay Types, DOM API, CSS Themes, Linkers
2009 GWT 1.6/GWT 1.7
GWT 2.0
EventHandlers, EMMA Support, WAR support, Parallelized Builds/Newer
browser support, IE8, GPE and AppEngine/DevMode, DraftCompile,
UIBinder, LayoutPanel, CodeSplitter, ClientBundle, CssResource
2010 GWT 2.1 RequestFactory, Editor Framework, Validation, MVP, Cell Widgets
2011 GWT 2.2/GWT 2.3
GWT 2.4
GWT Designer, HTML5 support/Better AppEngine
integration/Maven and RequestFactory enhancements
2012 GWT 2.5 SuperDevMode, Elemental, UiRenderers, FragmentMerging,
ClosureCompiler

20. Browsers

21. Browsers

22. xché
una codebase e
tante 'incarnazioni'
dell'applicazione.

23. Borntobe...
Why GWT? The beginnings of rich internet
applications started taking off in 2004-2005 with
Gmail/Google Maps. jQuery didn't even exist yet.
There was a vacuum for tools to build large scale
web applications, and leveraging the already mature
Java toolchain of IDEs, libraries, build tools, testing
frameworks, made good sense.
Ray Cromwell

24. Nowadays
● Plethora of languages compiling to js (..., python, C/C++,
Ocaml, Haskel, ...)
● Good and awesome js libraries & frameworks
Closure
Tools

25. Secondonoi
● non tutte le applicazioni sono uguali
● ed alle volte alcune richiedono strumenti inustitati

26. GWT-Boofcv GWT-Boofcv sample at:
http://goo.gl/3IJQgs

27. DEMO
http://picshare.jooink.com

28. MarkerBasedAR
http://code.google.com/p/gwt-webgl/
http://code.google.com/p/gwt-nyartoolkit/
http://picshare.jooink.com

29. Mobile(&tab)too

30. ComeFunziona
<video/>
<canvas/>
http://code.google.com/p/gwt-nyartoolkit/
Ny
HTTP

31. GWT GWT is a toolkit to develop Ajax web application with Java.
The programmer writes Java code and this code is translated
into HTML and Javascript via the GWT compiler.
The compiler creates browser specific HTML and JavaScript
to support all the major browsers correctly.

32. ToolsintheToolkit + GWTc, compiler Java to Javascript
+ Emulated JRE
+ Web UI class library (Widgets)
+ Eclipse Plugin, SpeedTracer, Designer
It's open source, completely free, and used by thousands of
developers around the world (in Google AdWords,Orkut,
Blogger,Groups)

33. Compiler GWT compiler
● java to javascript optimizing compiler
● translates java AST into js AST
● splits code into fragments to improve loading performance

34. Linker
● responsible for the final form of the generated js
xsiframe is the standard one
there are linkers for generating web-workers, gadgets, chrome
extensions, …

35. deferredbinding
Deferred Binding:
feature of the GWT compiler that works by generating
many versions of code at compile time, only one of
which needs to be loaded by a particular client during
bootstrapping at runtime.
Each version is generated on a per browser basis, along
with any other axis that your application defines or uses.
RPC Calls
Widgets tuned for specific browsers
Internationalization

36. deferredbinding
Deferred binding has several benefits:
● Reduces the size of the generated JavaScript code
(downloaded by each client) - including just the code needed to
run the browser/locale instance (used by the Internationalization
module)
● Automatic generation of code (saving development time) to
implement an interface or create a proxy class (used by the
GWT RPC module)
● Since the implementations are pre-bound at compile time,
there is no run-time penalty to look up an implementation
in a data structure as with dynamic binding or using virtual
functions.

37. EmulatedJRE GWT includes a library that emulates a subset of the Java
runtime library.
http://www.gwtproject.org/doc/latest/RefJreEmulation.html
InputStream
Threads ?

38. JNSI GWT borrows from the Java Native Interface (JNI) concept to
implement JavaScript Native Interface (JSNI).
Writing JSNI methods is a powerful technique, but should be
used sparingly because writing bulletproof JavaScript code is
notoriously tricky.
Needed for JSO (Javascript Overlay Types)

39. JNSI
public static native void alert(String msg) /*-{
$wnd.alert(msg);
}-*/;
$wnd: the root browser window GWT widgets are being
rendered to
$entry(..): method that makes code reentry safe.
http://www.lustforge.com/2012/11/11/gwt-jsni-variables-an-exhaustive-list/
http://www.gwtproject.org/doc/latest/DevGuideCodingBasicsJSNI.html

40. Widgets UiComponents
http://www.gwtproject.org/doc/latest/RefWidgetGallery.html
2.0+ LayoutPanels
http://www.gwtproject.org/doc/latest/DevGuideUiPanels.html#LayoutPanels
from the Jul 2013 - GWT Meetup
What are some of pain points or decisions bad in hindsight?
...
● Bad out of box UI
...
SmartGWT, GXT

41. UiBinder
● The UiBinder is a framework designed to separate Functionality and
View of User Interface.
● The UiBinder framework allows developers to build gwt applications as
HTML pages with GWT widgets configured throughout them.
● The UiBinder framework makes easier collaboration with UI designers
who are more comfortable with XML, HTML and CSS than Java source
code
● The UIBinder provides a declarative way of defining (parts of the)
User Interface.
● The UIBinder seperates the programmic logic from UI.
● The UIBinder is similar to what JSP is to Servlets.

42. UiBinder ● DSL (xml) to lay-out (declaratively) widgets
● no loops, no conditionals, no if statements
● UiBinder allows you to lay out your user interface.
● (offers direct support for internationalization)

43. GWT-RPC
Lets the client and the server to exchange
java objects over http.

44. Thanks
Alberto Mancini
alberto@jooink.com
Francesca Tosi
francesca@jooink.com