News

Google To Unveil GWT 1.5 at Developer Conference

• By John K. Waters
• May 27, 2008

The free GWT is an open source development framework aimed at Web application builders who want to use the Asynchronous JavaScript and XML technique (Ajax) without having to learn JavaScript. Developers use the toolkit to write their applications using Java, and then the GWT compiles that code into highly optimized JavaScript, explained Google engineering manager Bruce Johnson, co-creator of the GWT.

This version of the GWT will offerfull support for Java 5, including generics and annotations, Johnson said, as well as new features designed specifically to support the development of high-performance applications. Among these is a new set of compiler optimizations; using the GWT 1.5 to write Java code compiled into JavaScript is faster, Johnson said, than writing the JavaScript code by hand. The new GWT also comes with a set of API libraries, including one that supports the Google Gears online/offline browser extension.

Perhaps most important, GWT 1.5 solves the browser compatibility problems that plague JavaScript users, and which are becoming more of an issue as developers push the capabilities of Web applications, Johnson said. JavaScript's lack of modularity makes sharing, testing, and reusing Ajax components problematic, he explained.

Browser compatibility is no small issue for developers, said Ray Valdes, research director in industry analyst firm Gartner's Web services group. "It has only been in the last couple of years that browsers have reached the level of consistency and compatibility that allows you to write to standards, rather than the individual browsers," he said. "In the past you sort of had to developer for Microsoft's Internet Explorer and just forget about everybody else. Now you have Firefox growing in popularity. Apple's Safari actually has dominant market share on laptops costing more than a thousand dollars. And you have the mobile browsers."

The GWT is one of about 150 Ajax toolkits currently available to Web developers, but its Google pedigree is likely to send it toward the head of the line, Valdes said. He ranks it among the top toolkits, along with Dojo (which he ranks number one, in terms of developer usage), Prototype, jQuery, Mootools, and Ext JS.

"Of course, everybody has an Ajax toolkit," Valdes said. "Microsoft has one called Atlas, even though they have ASP.NET. Adobe has one called Spry, even though they have Flex. Yahoo has one called the Yahoo User Interface Library (YUI), which of this group is the one that is the most complete, and powerful, and gets the most developer support. None of these are money makers, they're not strategic, they're not always formally supported, and they can be directly competitive with the vendors other products."

Google has a leg-up because of its brand name, Valdes said, but also because the search giant "showed the world how Ajax could be used," with landmark applications such as Google Maps and Gmail. Google's own developers used the GWT to create Google Maps, Johnson commented.

Alex Moffat, engineering manager at Lombardi Software, will be speaking at the Google I/O event. Lombardi used the GWT to create a high-performance, collaborative diagramming tool, which is part of the company's Web-based process-documentation tool, Blueprint. "We're basically a Java shop," Moffat said. "That's what we're experts in. Learning JavaScript just wasn't practical for us."

Lombardi's developers initially created an alpha version of the tool using Dojo, but they found it difficult to do things like refactor. Also, its tooling didn't stack up to the available Java tools. And in the end, it just didn't integrate with the company's existing tool chain.

In 2007, Moffat's crew switched to GWT. "Using GWT, you don't have to know the JavaScript generated by the GWT compiler," he says, "just as when you're writing Java you don't have to understand the byte code the JVM uses."

To give attendees at his conference session an idea of the size of the application created with the GWT at Lombardi, Moffett has been counting lines of code. "If you exclude all white space, all comments, and all lines with single breakers on, there are 36,000 lines of code compiled with the GWT compiler. It's big."

This is Google's second major developer event. Last year the company sponsored its first Developer Day, which involved 10 cities around the world. The company is expecting 2,500 attendees at the San Francisco conference, which will offer two days of in-depth, technical sessions on building the next generation of Web applications with Google and open technologies. Technical sessions will cover, among other topics, OpenSocial, the Google App Engine, Android, the Google Maps API, and the Google Web Toolkit.

The "I/O" in the conference title is a play on input/output that actually stands for "Innovation/Open."