Google Web Toolkit: Towards a better web

Posted by Bruce Johnson and Dan Peterson, Google Web Toolkit team

We're very pleased to tell you that the Google Web Toolkit (GWT) is no longer in beta as of today's release of GWT 1.4. For Java developers who have used GWT to create high-end web applications over the last year, this may not seem all that surprising. But if you haven't yet heard the story behind GWT, this seems like the perfect time...

If you've been in the technology industry for a while, you probably remember when enterprises and software vendors had to think pretty hard about whether to develop locally-installed desktop applications or web-based browser applications. These days, whether you're building mashups, gadgets, or full-blown applications, it's a no-brainer: the browser is the delivery platform of choice. However, users expect more from the up-and-coming generation of web applications than the simple click-and-wait of yesterweb. And if you're a web developer, you know that this requires AJAX, the cluster of technologies including JavaScript and dynamic HTML that can make browsers do backflips.

But the stark reality of AJAX applications is that, although they can deliver sexy features and great usability, they are unusually hard to engineer. Browser quirks and the anything-goes nature of JavaScript will inevitably frustrate even the most dedicated developers and add risk to your schedule with every line of code written. If you do eventually manage to construct a complex AJAX application that works, you're likely to find that maintaining it over time can be a major challenge. And all that doesn't even scratch the surface of testing, optimizing, securing and internationalizing your application. (If you are currently working on an ambitious AJAX project and haven't yet come to this conclusion, please re-read this post in six months when you're further along!)

We've learned a lot from our experiences building web applications, and we're happy to share the tools we've created. Google Web Toolkit is an open source project that helps Java developers harness the richness of AJAX in a cross-platform, web-friendly environment. The magic trick is that GWT cross-compiles Java source code into standalone JavaScript that you can include in any web page. Instead of spending time becoming JavaScript gurus and fighting browser quirks, developers using GWT spend time productively coding and debugging in the robust Java programming language, using their existing Java tools and expertise. Naturally, GWT is also a great way to easily take advantage of the latest-and-greatest Google APIs and browser enhancements, such as Google Gears.

In addition to making debugging far easier, GWT's unique compilation-based approach to AJAX has the nice property that it rewards developers for good software engineering practices. Java source code that is clear and organized can be easily optimized by the GWT compiler, which is a nice antidote to the frequent hack-and-slash approach that's all too common in JavaScript development. As your application grows, the GWT compiler begins to pay off in even bigger ways. Unused code is automatically removed so that scripts are smaller and pages load faster. Complex code can be automatically coalesced and simplified. Most importantly, because the Java language is statically typed, many common errors can be caught during development rather than production. You can observe the high-performance results yourself in GWT's sample Mail application.

Technical details aside, GWT makes it easy to develop fast, friendly web apps that users love — which is, after all, the point.

Download GWT 1.4.