Posted byBruce Johnson, Engineering Manager - Thursday, August 28, 2008at4:14:00 PM
We're happy — no, ecstatic — to announce that GWT 1.5 is now officially released and available for download. Download GWT 1.5
GWT 1.5 delivers what we think are an impressive number ofimprovements, about four hundred issues if you're counting. We're alsohappy that one of those is issue 168, our most-requested feature, Support for Java 5.
We've blogged about several of the new features already. Now that it's official, let's recap and expand the list a bit...
Java 5 language support and enhanced JRE emulation 增强对Java 5 JRE的模拟
You can now use Java generics to add clarity and type safety to your client-side Java source.Generics also greatly simplify the definition of GWT RPC services — no more @gwt.typeArgs.
Java泛型支持
Simplify your code with for-each loops, autoboxing, static imports, and enum types.
for-each, 枚举,自动装箱，静态导入。。。
Subsystems such as RPC, image bundles, internationalization, and benchmarking now use proper annotations.To maximize code re-use, the GWT compiler also ignores unrecognized annotations, such as those required by JPA, that typically appear on types shared between the client and server.
RPC,国际化等功能可以采用annotation了
New JRE emulation classes have been added including StringBuilder, TreeMap, LinkedHashMap, and other popular utility classes.
StringBuilder, TreeMap, LinkedHashMap等JRE新类的支持
Assertions are now optionally supported in web mode. If you invoke the GWT compiler using the -ea flag, assert statements in your code will be retained in the compiled JavaScript.This can be helpful during QA cycles.
assert支持
Performance optimizations and easier JavaScript interop
The GWT compiler has gotten smarter. It now does comprehensive method inlining, which can eliminate signficant overhead due to function calls.Developers using GWT 1.5 release candidate builds have reported speedups of up to 2x, especially in performance-sensitive areas of their code. We've even heard from end users that apps compiled with GWT 1.5 just feel faster. Admittedly, feels faster isn't a quantifiable benchmark, but we sure like the sound of it. 速度最高是前一版本的2倍
The venerable Tree widget has gotten much faster in GWT 1.5. In tests, we've measured huge improvements across the board, including 5x and 10x speedups on IE7 and IE6, respectively.
Tree 控件在Ie6和Ie7上有巨大的性能飞跃
With new JavaScript overlay types, you can seamlessly and efficiently integrate with objects originating in handwritten JavaScript. Overlay types also provide a particularly elegant new way to interact with JSON data from GWT.
Javascript Overlay功能，让GWT和手写的Javascript更平滑的交互
The new Linker subsystem gives you total control over your code'spackaging and bootstrap behavior so that you can deploy GWT output intoany context where JavaScript is relevant (think Gadgets, Firefoxextensions, Greasemonkey scripts and Gears worker threads). If itsounds complicated, don't worry: most GWT users can simply re-use thebuilt-in linkers. But it's nice to know you can create your own if youneed to. See Bob Vawter's Google I/O talk on Linkers for the theory, and Ray Cromwell's GWT Extreme! talk for some enlightening real-world examples.
一个新设计的GWT编译器
Prettier widgets, better DOM, accessibility, and bi-di 更美观漂亮的控件,新的跨浏览器的DOM类, bi-di.....
The original KitchenSink sample has been retired in favor of a new sample called Showcase. In addition to demonstrating a wide variety of GWT features — widgets, themes, animation, history, accessibility, internationalization and bi-di to name a few — Showcase helps developers understand how code and CSS fit together by providing the source for each showcased feature.
Experienced GWT developers know and like the fact that widgets rely almost exclusively on CSS for styling. However, prior to GWT 1.5, GWT projects did not include a stylesheet by default, giving developers new to GWT the unfortunate impression that GWT widgets were inherently ugly.With this release, we're introducing three nice-looking default CSS themes you can use as a starting point for your own designs.
Not only are the standard GWT widgets prettier in this release, they're more functional. The major widgets such as Tree, MenuBar, and TabPanel now support ARIAfor enhanced accessibility. In addition, widgets now supportbi-directionality so that UI works properly for right-to-leftlanguages.(You can see all this in action in the Showcase sample.)
A new cross-browser DOM packagemaps the entire set of W3C bindings onto GWT-compatible Java classes.After all, not every project needs full-on widgets.If you want to do low-level DOM programming or you're writing newwidgets, you'll really like these new classes.It feels as if you're writing JavaScript DOM manipulation code butbetter: you get reliable code completion, easy debugging, cross-browserportability and compiler optimizations.
Those are some highlights. The (new) GWT Developer's Guide has a more detailed explanation of GWT 1.5 changes, including notes about a few breaking changes you'll want to be aware of.
For further information or for help getting started with GWT, you may find the follow links helpful:
If you're new to GWT, the Getting Started Guide takes you through a very quick example of installing and using GWT.
There's a new in-depth GWT tutorial that guides you through the process of building and enhancing an application from scratch.
