Google Web Toolkit
|Initial release||May 16, 2006|
|Stable release||2.7.0 / November 20, 2014|
|Operating system||Linux, Windows, OS X|
|License||Apache License 2.0|
GWT emphasizes reusable approaches to common web development tasks, namely asynchronous remote procedure calls, history management, bookmarking, UI abstraction, internationalization, and cross-browser portability.
|GWT 1.0||May 17, 2006|
|GWT 1.1||August 11, 2006|
|GWT 1.2||November 16, 2006|
|GWT 1.3||February 5, 2007|
|GWT 1.4||August 28, 2007|
|GWT 1.5||August 27, 2008|
|GWT 1.6||April 7, 2009|
|GWT 1.7||July 13, 2009|
|GWT 2.0||December 8, 2009|
|GWT 2.1.0||October 19, 2010|
|GWT 2.2.0||February 11, 2011|
|GWT 2.3.0||May 3, 2011|
|GWT 2.4.0||September 8, 2011|
|GWT 2.5.0||October 2012|
|GWT 2.5.1||March 2013|
|GWT 2.6.0||January 30, 2014|
|GWT 2.6.1||May 10, 2014|
|GWT 2.7.0||November 20, 2014|
In 2011 with the introduction of the Dart programming language, Google has reassured the GWT community that GWT will continue to be supported for the foreseeable future, but also hinted at a possible rapprochement between the two Google solutions for "structured web programming". They've also admitted however that a number of engineers previously working on GWT are now working on Dart.
In 2012 at their annual I/O conference, Google announced that GWT would be transformed from a Google project to a fully open sourced project. In July 2013, Google posted on its GWT blog that the transformation to an open source project was complete.
Development with GWT
GWT applications can be run in two modes:
- Development mode (formerly Hosted mode): The application is run as Java bytecode within the Java Virtual Machine (JVM). This mode is typically used for development, supporting hot swapping of code and debugging.
Several open-source plugins are available for making GWT development easier with other IDEs, including GWT4NB for NetBeans, Cypal Studio for GWT (an Eclipse plugin), and GWT Developer for JDeveloper. The Google Plugin for Eclipse handles most GWT related tasks in the IDE, including creating projects, invoking the GWT compiler, creating GWT launch configurations, validation, and syntax highlighting.
The major GWT components include:
- GWT Development Mode
- JRE emulation library
- GWT Web UI class library
- A set of custom interfaces and classes for creating widgets.
- Dynamic and reusable UI components: programmers can use pre-designed classes to implement otherwise time-consuming dynamic behaviors, such as drag-and-drop or sophisticated visual tree structures.
- Simple RPC mechanism
- Browser history management
- Support for full-featured Java debugging
- GWT handles some cross-browser issues for the developer.
- Unit testing integration
- Support for Internationalization and localization
- HTML Canvas support (subject to API changes) 
- Support for using Google APIs in GWT applications (initially, support for Google Gears)
- A number of libraries are available for GWT, by Google and third parties. These extend GWT's features.
Many common widgets not found in the GWT have been implemented in third-party libraries, such as Sencha GXT (formerly Ext GWT), GWT Component Library, GWT-Ext, GWT Widget Library, GWTiger, Rocket GWT, Dojo, SmartGWT etc.
GWT uses or supports Java, Apache Tomcat (or similar web container), Eclipse IDE, Internet Explorer, and Internationalization and Localization. Java-based GWT RIAs can be tested using JUnit testing framework and code coverage tools. Because GWT allows compile time verification of images, CSS, and business logic, many common development defects are automatically discovered without need of the manual testing commonly required by RIAs.
On Dec 08, 2009 Google launched Google Web Toolkit 2.0 with Speed Tracer.
Version 2.0 of GWT offers a number of new features, including:
- In-Browser Development Mode (formerly known as Out Of Process Hosted Mode, OOPHM): prior to version 2.0, hosted mode used to embed a modified browser to allow running the bytecode version of the application during development. With version 2.0, hosted mode, renamed "development mode", allows using any (supported) browser to view the page being debugged, through the use of a browser plugin. The plugin communicates with the development mode shell using TCP/IP, which allows cross platform debugging (for example, debugging in Internet Explorer on Windows from a development mode shell running on a Linux machine).
- Declarative User Interface: using an XML format, the new feature known as UiBinder allows the creation of user interfaces through declaration rather than code. This allows clean separation of UI construction and behavior implementation.
- Resource bundling: the ClientBundle interface will allow resources of any nature (images, CSS, text, binary) to be bundled together and transferred in one download, resulting in fewer round-trips to the server and hence lower application latency.
Since the new development mode removed most platform-specific code, the new version will be distributed as a unique archive, instead of one per supported platform as was the case with previous versions.
As a general framework for making web apps, GWT is also capable of being used as a framework for making mobile and tablet apps, either by making the needed widgets and animations from scratch, or by using one of the mobile frameworks for GWT. An HTML5 app written in GWT can have separate views for Tablets and Mobile phones.
Some of the most common mobile GWT libraries
- Dart (programming language)
- Google Plugin for Eclipse
- Showcase/Live Demo of GWT Features
- Google Code
- Comparison of web application frameworks
- GWT-Platform GWTP, an annotation based Model-View-Presenter framework for GWT built by Arcbees
- Errai is a GWT-based framework for building rich web applications using next-generation web technologies. Built on-top of ErraiBus, the framework provides a unified federation and RPC infrastructure with true, uniform, asynchronous messaging across the client and server.
- SmartGWT, a GWT framework with a comprehensive widget library and server side databinding capabilities
- Vaadin, uses GWT as a "rendering engine" on the browser side of its server-based web apps written in Java.
- Sencha GXT, GWT port of the popular Ext JS UI Framework commonly used in Enterprise applications.
- Crux Framework is an open source GWT-based component framework for fast development of web and mobile applications.
- Pyjamas Pyjamas, a port of GWT to Python
- RubyJS, a port of GWT to Ruby
- ZK, a similar framework, which is also written in Java.
- GwtPHP, Backend for GWT in PHP.
- Scala+GWT, compile Scala code for the browser via the GWT toolchain.
- "GWT Name Use Policy". Google. Retrieved 2014-04-23.
- "Development Mode will not be supported in Firefox 27+". groups.google.com.
- "GWT Developer Plugin no longer works with Chrome on Linux". groups.google.com.
- "Google Web Toolkit License Information". Google. February 23, 2007. Retrieved 2007-09-25.
- "Google Web Toolkit Release Archive". Google. Retrieved 2007-09-25.
- Olson, Steven Douglas (2007). Ajax on Java. O'Reilly. p. 183. ISBN 978-0-596-10187-9.
- Ramsdale, Chris. "Google Relaunches Instantiations Developer Tools".
- "Google Web Toolkit Blog: GWT and Dart". Googlewebtoolkit.blogspot.com. 2011-11-10. Retrieved 2013-06-16.
- Vaadin to Support Google Web Toolkit (GWT) Development. vaadin.com (2012-06-29). Retrieved on 2014-05-15.
- Google Web Toolkit Blog: GWT News. Googlewebtoolkit.blogspot.com (2013-07-15). Retrieved on 2014-05-15.
- GWT mission statement
- Debugging in Development Mode
- Cypal Studio for GWT
- Perry, Bruce W (2007). Google Web Toolkit for Ajax. O'Reilly Short Cuts. O'Reilly. pp. 1–5. ISBN 978-0-596-51022-0.
- "GWT Javadoc".
- "Widget List". Google. Retrieved 2012-05-21.
- GWT Project. GWT Project. Retrieved on 2014-05-15.
- "Google I/O 2012 - The History and Future of Google Web Toolkit". GoogleDevelopers. Retrieved 2013-03-18.
- Toubassi, Garrick. "Going under the hood of Inbox". Official Gmail Blog. Retrieved 22 November 2014.
- Introducing Google Web Toolkit 2.0, now with Speed Tracer
- "GWT 2.0 milestone 1 announcement". Amit Manjhi. Retrieved 2009-10-05.
- "Vaadin FAQ". Vaadin Ltd. Retrieved 2014-05-11.
- "Building parsers for the web with JavaCC & GWT (Part one)". Chris Ainsley. Retrieved 2014-05-04.
- Dewsbury, Ryan (December 15, 2007). Google Web Toolkit Applications. Prentice Hall. p. 608. ISBN 978-0-321-50196-7.
- Chaganti, Prabhakar (February 15, 2007). Google Web Toolkit: GWT Java Ajax Programming. Packt Publishing. p. 248. ISBN 978-1-84719-100-7.
- Geary, David (November 17, 2007). Google Web Toolkit Solutions: More Cool & Useful Stuff. Prentice Hall. p. 408. ISBN 978-0-13-234481-4.
- Hanson, Robert; Adam Tacy (February 7, 2013). GWT in Action (2nd ed.). Manning. p. 643. ISBN 978-1-935182-84-9.
- Cooper, Robert; Charlie Collins (May 12, 2008). GWT in Practice. Manning. p. 376. ISBN 978-1-933988-29-0.
- GWT homepage on Google code
- Official GWT blog
- Official GWT forums
- Google Web Toolkit Incubator
- Conference on GWT organized by Addison-Wesley, Prentice Hall and Pearson Education