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Is Anyone Using the Google Web Toolkit?
eldavojohn writes "After seeing some applications from Google and participating in the Google Codejam (which seems to be built using the GWT), I kind of expected to see websites spring up left and right based off the GWT. Well, it's been a year and a half since they open sourced it and I have to admit that I am more than a little disappointed by its low profile in the UI community. I've been trolling their blog and have seen a few books out on it. But the one thing I'm not seeing is its use outside of Google. I've worked through the examples and tutorials at home and though I've been impressed with the speed, I am disturbed by the actual result — a whole ton of generated Javascript. But this is the first UI technology I've found where I can write in the native language of the server (Java) to generate and unit-test the UI code. Aside from Google's use and the games of Ryan Dewsbury like KDice & GPokr, does anyone know of major sites using the GWT? If you don't and you've used it yourself, why isn't it taking off? Is it too immature? Is it a solution to a problem that already has too many solutions? Is it fundamentally lacking in some way?"
Because a big company open sources something we're supposed drop what we're doing and run to the next best thing?
JavaScript libraries and toolkits multiply faster than rabbits, there's a new "framework" coming out each week, and some of them had strong developer support (i.e. people willing to answer my stupid questions in forums) long before Google came out with their stuff.
Not that it's bad or anything, but in the end it's all JavaScript anyway, and learning two different ways to get to the same goal (an interactive site) is generally pretty low on everybody's priority list.
Are you using Google Sparse Hash by the way? Why not?
is that everyone wants to roll their own.
How we know is more important than what we know.
To me, the biggest problem is abolutely no fallback to non-javascript browsers. I'm not so much worried about users, but search engine bots won't be able to spider me and drive traffic to me.
-Bucky
We built a Proof of Concept Report Designer and Report Viewer on top of BIRT using GWT for the interface. It had some cool features, like multi-user real-time report development, versioning, and tie ins to the commercial report repository that the company that built BIRT sells. It had a real nice WOW factor to it, but in the end, it was just a pretty POC that we could show at conferences, it would never replace the desktop version due to responsiveness (imagine, an Eclipse app that is more responsive than something else...) IMHO, web technology is just catching up in the UI space to where desktop apps were like 15 years ago, and Web 2.0 is still a tacky buzzword. To do some things that are trivial in a desktop app requires a lot of convoluted steps (callbacks, etc). And even things that would be done the same way still requires a network round trip to get information that desktop apps don't suffer (simple tasks like dynamic drop-down or list population). GWT is a step in the right direction, and the ability to debug in an IDE both client and server side components is very nice.
I'm a long time web developer but I've never even cracked open the box on GWT, so take this with a grain of salt.
The idea of depending on generated javascript scares me. I'm against writing Javascript in Java, Ruby, Python or anything else. Javascript is just too much of a beast to debug to leave everything up to an opaque framework, and I want to be able to get my hands dirty. I like the smaller and more traditional open-source style frameworks. Prototype, jQuery, MooTools, even Dojo just scare me a lot less.
It could be totally irrational, and it also could be the fact that I tend to build web applications that need minimal state and pretty basic AJAX interactions. Nothing anywhere near as dense as, say, Gmail. If the right project came along I'd definitely give it a more serious look.
Probably the most popular social website in Lithuania uses GWT - www.one.lt.
My experience with GWT is rapid prototyping. Overall, I like playing around with GWT. It's a great way to quickly dynamic web sites without wading through the mess that JavaScript is. Considering that I do other kinds of software on a day-to-day basis; GWT has a learning curve that's gentle enough to allow me to write powerful UIs as a weekend project.
GWT's integration with Eclipse; especially its debugger, is a significant advantage. Its compiler is also another advantage. I tend to shy away from JavaScript because I prefer compiled environments with rich debuggers.
I think GWT's long-term strengths could be its maintainability, although someone who is experienced with both JavaScript and GWT will be better off making such a judgment. I have not written a large, multi-developer GWT application; thus I do not know what kind of complexities arise in such an environment.
GWT has an odd deployment system that's designed to take advantage of HTTP caching. Compiled javascript files are named based on a hashing algorithm, thus a web server can be optimized to instruct the browser to only download code when a new version is compiled. This makes storage of compiled JavaScript difficult for some deployment scenarios, because the files always change.
I've been reading the mailing list for about a year, and in general, it tends to have a lot of novices and hard-core Java developers. There's a lot of talk about using various Java frameworks within GWT. I get the impression that, even though GWT is Java-based, using frameworks like Spring or Hibernate is like ramming a square peg down a round hole.
Some novices don't understand that GWT doesn't run under the JRE, or assume that GWT can somehow magically make their favorite library run in the browser. GWT compiles Java into JavaScript; it does not deal with Java bytecode (except in its debugger.)
There's also a lot of talk about using various RPC / Remoting protocols when served from a Java web server. It seems that some Java programmers like that they can keep a simple layer between code running in the browser and code on the server. I personally avoid these layers and stick with simple AJAX calls into PHP or my custom-written C# server.
I wrote this in GWT as a learning exercise: http://andrewrondeau.com/com.Memmexx.GearPod/GearPod.html
Now, you might think "wouldn't it be a cool idea to integrate an MP3 search engine into your demo?" I did, but it's locked behind closed doors because I don't want to get sued! (It turns out that the folks at Seeqpod got sued after I completed the version with the search engine.
No, I will not work for your startup
On a personal level, I'd rather see the effort spent learning GWT applied to learning Javascript and the web technologies instead. There are a lot of frameworks out there, but none of them are actually needed in 90% of the cases. What we actually need are programmers who know how to write maintainable and highly interactive Javascript components for their sites. Such knowledge allows them to get the job done faster than mucking about with Yet Another Framework(TM) designed to take a cannon to the problem of killing a fly.
It's not learning Javascript that's the big obstacle to coding your own solutions sans framework; it's dealing with the browser compatibility issues. Frameworks largely compensate for that.
If you write your own non-trivial Javascript code, you have to test on IE 6/7/8, FF 2/3, Opera 9.whatever, Safari 2/3, etc etc etc etc.
OtakuBooty.com: Smart, funny, sexy nerds.
I've been on a project using GWT in 2007, been quite successful. If you want to see an example that is public run over to Parlays.com, they have a Flex and a GWT version.
If you want to write clean code check out my blog on TDD with GWT: http://is.gd/1156.
With the 1.5 release they did some very promising improvements.
So you're right if you say it is not mainstream, but to say nobody is using it is exaggerating. Just be patient, GWT will continue to grow.
Show a man some news, distract him for an hour. Show a man some mod points, distract him for the rest of his life.
Here's a hint for you: Use Glassfish. Your life will be about 1000x easier.
Here's another hint: No matter what anyone tells you, AVOID JAVA SERVER FACES LIKE THE PLAGUE. The API will not help you.
Hope that helps. :-)
Javascript + Nintendo DSi = DSiCade
We have used it for a fairly big internal application for one of our clients. Given we wanted ajax rather than a typical rich client, the main advantage of GWT was that we could program in the same language end-to-end.
We managed to avoid a lot of boilerplate code by using the same data class definitions (POJO's) in the server and client. So an object might be created by hibernate from a database record, copied to the client, displayed and edited, copied back to the server, manipulated there and finally updated in the database via hibernate.
The main omission in GWT is a good framework for binding data to UI elements. Because there is no introspection available in the GWT client environment, it is hard to do this in a generic way. We solved the basic problem by generating class and property descriptors during the usual hibernate code generation step. We then created a UI-POJO binding framework that picks up and uses these descriptors. Again avoiding a lot of boilerplate.
Our code for all this is here: http://code.google.com/p/gwt-hibernate/
I'd say GWT worked out pretty well.
You start with the assumption it should be widespread, and are disappointed because it is not. Which leads to the question, what leads you to that assumption?
As a student, don't bother learning frameworks with the idea that you will use them later. There are only two good reasons to learn a framework. The first is to use it right away on a project you want to get done. The second is to get experience with frameworks in general and particular types of frameworks. It is valuable to be able to:
Knowing a framework is, in itself, pretty useless unless you are going to use it right away or apply for one of those mythical Monster.com jobs where companies hire people to work with version 2.37a of Ridiculously Specific Technology Z. I don't know of any companies that actually hire that way unless they need a consultant to work with a legacy system whose developers have long since disappeared. In other words, you won't be hired for your experience with a specific framework until that framework is obsolete.
Now, setting aside the proper way to study frameworks, why are you even thinking about frameworks as an "investment" at your age? You sound like you're in way too much of a hurry. If you learn one distributed N-tier application framework, one web application framework, and one rich client application framework, then you will have much more industrial-type experience than most developers ten years older than you. The downside is that industrial-type experience, while it helps you make better decisions about large-scale software development, also tends to dull your brain. If you're already focusing on frameworks in college, you're going to be burned out and useless by the time you're thirty. You'll end up quitting and starting over from scratch in a new career, just to get away from software. Unless you're just one of those precociously responsible (*cough* boring *cough* *cough*) kids who tracked his gas mileage in high school and thought the coolest thing about the Science Fair was having an excuse to wear a suit and gesture at graphs.
In college, you should be implementing your own language, becoming a whiz at Emacs Lisp, mucking with kernel modules, starting your own web business, building natural language parsers, and doing all the other silly, vain, perfectly useless (Emacs Lisp excluded) things that end up making you into a smart, versatile programmer.
As a software development *student*, you should be focusing more on the concepts, on engineering problem solving, and on reasoning skills than on the specific technologies.
As a software engineering professional, I learn the tools that I need to effectively do my job. I learn things that look interesting and applicable to whatever it is I am doing. Thus, I work with the GWT and with AJAX because I decided that's what I needed in order to tackle a problem we were having. As a senior engineer who is engaged in the hiring process, I care more about that you can think than that you happen to have seen and worked with twelve dozen technologies by the time you graduated. As a job posting I saw recently says:
You can't predict it and the specific tools will change tomorrow, so as a student I would generally say that learning it--unless it is for a specific project or class of projects, or because it contains a concept or problem solving idea that you want to learn--is a waste of time. I learned R back in school because it was more efficient than using Minitab for multivariate statistics and for statistical modeling, not because it was out there and I needed to put it on my resume. On the latter point, I still think learning Prolog and LISP were extremely valuable despite that I never use them professionally and will probably never use them professionally.
Incidentally, if you are a good engineer, the language doesn't matter. If you are a bad engineer, the language still doesn't matter. *Problem solving* counts for more in the long run than bullet points.
Integrate Keynote and LaTeX
Apart from a few niche Web 2.0 sites, most websites are still built using tried and tested backend tech, and laid out using HTML, CSS and some graphics. GWT is pretty much doing everything using Javascript and a little bit on the server side serving xml/json. Not everyone needs AJAX. Most sites need to be able to work without it (for accessibility, backwards cinpatibility and non-javascript visitors), so unless its capable of adding really useful features (cases of which are few and far between) AJAX and GWT are just not necessary. Its nice if you can have it, but its a luxury you don't actually require for a usable website / web application.
Caesar si viveret, ad remum dareris.
When people are looking for an Ajax toolkit, the Google name often gets it onto the selection "short list", but that doesn't automatically assure that it will be the final choice. Many corporate IT organizations insist upon commercial support for any software that goes into their business-critical applications. Of course, Google does not provide such support. In those situations, GTK will be ruled out for business reasons, independent of its technical merits. The net result is that there are numerous sites built on GTK, but the large variety of choices means that no single framework or toolkit has yet emerged as a favorite.
Because I needed a website with a high level of interaction. The client asked for enabling disabling of various things on a widget, some bells and whistles,but nothing fancy. In the beginning I wrote the code for this using javascript, hand coded the whole thing. But change requests, and much more important than that, browser compatibility problems cost me a lot of time. GWT fixed this aspect. Mostly compatible with all major browsers, and being much more experienced in Java than in js, I became more productive.
However, I should have limited my implementation to a single widget, and that was my mistake when using GWT. Use a plain jsp page, attach the widget to a div, and be done with it. Instead I've built the whole thing on GWT, and later fell in a position where I can not easily add very simple stuff. The usual GWT app is one single js chunk, which navigates to different pages by hiding and showing things on a page. This requires a little getting used to, and I've implemented more flexible things like pulling html via remote calls etc. But in general, mixing GWT with a more server side oriented technology (asp.net, jsp, jsf etc...) looks like a better approach now. But when you have to build a slightly complex interface where there are trees, enabled disable compoenents, users adding, removing things to a list etc, GWT serves well. I guess the secret is in the balance, just use it at the necessary level, no more. I could have used Flash, but that'd be a total pain for multiple reasons. (a lot of reasons actually)
http://en.wikipedia.org/wiki/Progressive_Enhancement
When building sites I start with the plain HTML, make it usable, and then use statically linked JavaScript to start rewriting the page with the bells and whistles when the page loads. That way, if JS is not enabled the reader doesn't get the 'enhancements' but the core functionality is still there.
Stupid flounders!
I couldn't agree more. There 2 very different ways to use Ajax:
1) have a traditional site and embed small "Ajax goodies" here and there, like digg does with comments.
2) have a 100% Ajax site, like GMail.
Cleary, GWT is good for (2), not (1). Now ask yourself, how many full Ajax sites do you know? GMail, Yahoo mail, a couple more? So it's not a problem with GWT, it's just that the idea of a full Ajax site is not suitable for the open web, it is much more useful for intranet and web-apps use.
Theoretically...
Number of Java developers > Number of Flash developers > Number of Silverlight developers
Number of Javascript capable browsers > Number of Flash enabled browsers > Number of Silverlight enabled browsers.
Which is a good idea, since Google has created a framework in a language that most developers are familiar with, for a platform that just about all web browsers support out of the box.
However...
Number of PHP hosting sites > Number of ASP hosting sites > Number of Ruby hosting sites > Number of Tomcat hosting sites
Which is probably one of the reasons why it's not doing so well.
GWT-RPC is excellent. It allows me to use the same data objects on client and server, and debug both from the same IDE. But it requires a Tomcat server.
Now if GWT is able to compile the server portion to easily deployable PHP code, this could lead to somewhere interesting.
I've recently spent a year with the GWT, and just a couple of months with Flex.
I would use Flex to flashify whatever dynamic parts of a standard html page I needed to for my next project. Everything that I'm trying to do in GWT could be done much faster in Flex... and when you are done in Flex, you are really done.
In the GWT, you have to be aware of what html each of the Java GWT widgets equates to... and then in the CSS, you have to work thinking about the resulting html. (FireBug makes it pretty easy.)
Cons for GWT 1.4:
- Long start-up times: web sites can take 8 seconds to show you their first page as the GWT javascript initializes.
- One imperfect CSS declaration, and you're having to debug IE6 / IE7 / Firefox / Safrai issues... Only very plain sites are insulated well from browser incompatibilities.
- Your site is all-or-nothing GWT. It's possible to use one GWT app to automate one part of a static page easily... but usually your whole site is 100% GWT, with no other static pages outside of the GWT's control.
- The AJAX mechanism on RFC-compliant browsers only lets you make two async requests at once... a third request is queued until one of the first two async requests returns... making it only asynchronous to an extent.
- I ended up having lots of html in my .java files, and using the HTMLPanel to turn that html into a GWT Widget. There are some parts of a web site that really do make more sense as HTML, and there's no easy way in GWT to keep the html separate (no templates!?!)
- The integration of GWT development can be done simply, but it can also grow to mirror the complexity of EJB style Java junk way too easily.
- IE needs special treatment (worth repeating.)
That said, it's probably the best way to create a web app for an iPhone right now, since there's no flash on the iPhone. (Please Adobe, I'd love it if you created an Air run-time for the iPhone!)
Pros of the GWT:
- it makes it easy to handle the back button and bookmarks.
- it can scale up to fairly large sites, and the smallest building blocks can be kept clean and small.
- the end user experience is a good one after that start-up delay.
- The GWT team has done lots of fantastic work, and in an open exchange... one of my coworkers has committed some changes to one of the supporting libraries.
Flex, on the other hand is designed to appeal to people who are weary from fighting CSS / browser incompatibility issues. In Flex, you still use CSS, but it works the way you would expect all the time. In Flex, you can also skin any compononent to look however you want, and then have a very clean top-level which wires up the various components with their skins. It's really beautiful... and best of all, when you're done, You're done! You don't even have to test on IE6! The learning curve is about the same, or a little harder, but it's all forward motion.
My next site is going to be 80% Django templates, with a good dose of mochikit (or dojo) for some dynamic parts, and a few Flex / flash applets sprinkled in where they make sense.
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I think the market has shifted a bit more than you're giving it credit for.
But it all depends on your niche.
We built our business on web retail and we still do an awful lot of it. And in that world, you simply cannot afford to lose a customer due to whatever whizbang technology you want to use at the moment.
But outside of retail is very different.
And the truth is, non-JS visitors and non-Flash visitors are the slimmest of minorities. 1-3% on average. If I was targeting the /. market I'd accommodate it. But for a general cross-section of the web? Javascript rules the day.
* Keyboard support to Menus and TabBars
* Added ARIA roles/states to MenuBar/MenuItem, Tree/TreeItem, TabBar/TabPanel, CustomButton/ToggleButton/PushButton
* Screen readers are now able to identify and speak the content of these widgets
* Improved tab navigation
* New API to set ARIA roles/states on Elements (still experimental)