GWT 1.4 release and out of beta

It's a really big day for Google Web Toolkit: GWT 1.4 is now available -- and, with more than a million downloads under our belt, GWT is no longer in beta!

What's new in GWT 1.4?

There's lots and lots of cool new stuff in GWT 1.4, so it's hard to know where to start. How about application performance?! This release includes several breakthroughs that make your compiled GWT code significantly smaller and faster. Many users are reporting that after a simple recompile with 1.4, their applications are up to 30% smaller and 20%-50% faster. And startup time in particular is now highly optimized thanks to a new bootstrapping technique and the availability of image bundles. To see the new hotness in action, try visiting the new-and-improved Mail sample a few times. It's darn fast the very first time you visit it, but subsequent visits are insanely fast. That's because, in addition to a fast initial startup, GWT code uses a clever caching technique to prevent applications from making unnecessary HTTP requests. As Joel Webber (Tech Lead of GWT Core Libraries) would say, "The fastest HTTP requests are those that do not, in fact, occur."

Here's a broad overview of the major enhancements:

New widgets and libraries

• RichTextArea, HorizontalSplitPanel and VerticalSplitPanel, SuggestBox, DisclosurePanel, PushButton, ToggleButton, and an enhanced Image widget make advanced applications easier than ever.
• ImageBundle automatically consolidates multiple images into a single HTTP request.
• NumberFormat and DateTimeFormat make easy work of complex internationalization and localization.
• You can finally use java.lang.Serializable with GWT RPC, and the GWT RPC server-side subsystem is no longer intimately tied to servlets. You can easily wire it into any Java back-end infrastructure. Spring fans, rejoice.
• A new JUnit-based benchmarking subsystem makes measuring and comparing the speed of code snippets as easy as writing unit tests.

New deployment options and optimizations

• Adding GWT modules to an HTML page is now simple: just add a tag.
• You can now include GWT modules across domains. Note that including scripts from other sites that you don't fully trust is a big security risk.
• External JavaScript files referenced from your GWT module load synchronously now, so script ready-functions are no longer needed.
• Auto-generated RPC whitelist files are now produced during compilation to help catch accidentally responding with objects that compiled GWT client code wouldn't be able to deserialize.
• The GWT distribution now includes a DTD for the GWT module XML format, making it easier to configure modules in an DTD-aware XML editor.

Additional details on these new features and bugfixes are in the blog post announcing the original GWT 1.4 Release Candidate.

For all you GWT veterans ready to download GWT 1.4, see the new FAQ section "How do I upgrade to GWT 1.4?" for step-by-step instructions on the update.

And for anyone totally new to GWT, on behalf of the awesomely cool developer community and the GWT engineering team at Google, welcome!