To what extent does a successful GWT developer need to be a fully fledged 'web developer'? - gwt

By 'web developer' I mean a software developer having a sound
understanding of web fundamentals (HTTP, HTML, CSS, JavaScript and
Ajax).
By 'successful GWT developer' I mean someone who can produce
high quality and polished looking GWT apps in timely fashion.
My department is gearing-up for a project that will require the development of a number of single screen RIA web apps. These will front enterprise server components implemented in Java. Our UI prototype was developed using ExtJS and was successful (in terms of speed of development and producing a professional, polished looking UI that integartes well with a service oriented API implemented using Spring-MVC + Jackson). However, in gearing-up to develop the actual product we have realised that our department's skills profile isn't ideal for ExtJS. We are strong on Java but relatively weak on web developers. The development of the UI prototype demonstrated that you really need fully feldged web developers to get to grips with ExtJS, since they will spend a significant amount of time grappling with CSS and JavaScript issues. As a result, the question has arisen as to whether we might be better off going with GWT (combined with a library that offers a level of polish comparable to ExtJS, such as SmartGWT). Obviously this assumes that GWT is significantly less demanding in terms of web development skills. To what extent would GWT + SmartGWT allow our Java developers to crank out high quality RIAs without them having to acquire anything more than a basic appreciation of the web fundamentals listed above?
If we decide to explore GWT further we'll do another prototype, but in the mean time it would be very interesting to hear the opinions of experienced GWT developers.

My experience is that you can get away with a lot without advanced web skills, but the end result is a pretty bland looking app, but even worse, you'll find yourself struggling to achieve all the dynamic effects you want.
As an example, my app has a DataGrid on the main tab. That could be done easily enough using pure GWT. But then I wanted to put a checkbox under the DataGrid widget that the user could use to select "single line mode", in which the rows are one line each -- any data in cells that would have word-wrapped just disappears at the edge of the cell. Hit the checkbox, and the rows collapse to one line each, then hit it again, and the row heights expand to whatever size is needed to display all the data in the cells. There isn't a method for that. What you have to do is adjust the row style of the DataGrid to add or remove the CSS element "white-space:nowrap;". So you add a ValueChangeHandler to a CheckBox widget (GWT skills) that modifies a CSS style of the DataGrid widget (web skills).
Without web skills, you'll find yourself hitting walls in trying to achieve the look-and-feel (and even dynamic behaviour) you want. Having said that, you can find these sorts of answers easily enough on the web. The key thing to remember is that just because GWT doesn't seem to have a method for something, that maybe it's really a web issue, not a GWT issue, and that you have to remember to think outside of the GWT box to solve your problem (instead of throwing up your hands, blaming GWT for lacking a feature, and hoping something like SmartGWT will solve all your problems).
The fact that every GWT widget has a plethora of methods for setting, adding, and removing styles, and the very rich integration via ClientBundles and UiBinder and the like, means that this was always the intent.

GWT is a very capable framework and can be used to produce great results such as Pictarine, but as the developers of Pictarine indicate:
Another thing that was not obvious to us when we started with GWT was that a java developer needs an intimate knowledge of HTML/CSS if he/she wants to go beyond the basic user interface provided by the GWT widgets.
I'm not quoting this to discourage anyone. Basic interfaces are indeed within reach with GWT without much HTML/CSS knowledge. GWT, however, leans on web languages and so in a non-trivial application familiarity with JavaScript, HTML, and CSS will come handy. Personally, using GWT has been continuously deepening my JS/HTML/CSS skills as I've been searching for ways to enhance my GWT projects, which in the end has been very rewarding.

Related

Best suite for GWT widgets

I am looking to build a GWT based web application. Being new to GWT, am looking for suites that provide the best GWT widgets (in terms of user experience, variety, styles, etc.), to help build a web app.
I have come across SmartGWT, but looking for other options/suggestions.
Thanks in advance!
I've done apps in both GWT and SmartGWT. My observations, for what it's worth:
SmartGWT has all sorts of cool features, out of the box. It's easy to be seduced by the SmartGWT showcase.
GWT is converging on SmartGWT, and quickly. For instance, the new DataGrid
can stand up against the SmartGWT ListGrid and come away looking good.
In order for GWT to look good though, there has to be real skill in the
developer. SmartGWT can make anyone look good, it seems, but to make
GWT shine takes skill.
Once you have that level of skill, though, there's no looking back.
GWT seems to me to be much more flexible, a consequence of the building-block approach. SmartGWT is more monolithic.
SmartGWT's design has some portability issues. I successfully took a pure GWT app I made and re-worked it (minimal effort) to run nicely in a BlackBerry PlayBook browser. I took a
SmartGWT app I had made at about the same time, and half the widgets
didn't work.
For an enterprise level solution I'm working on, I'm using pure GWT and I don't regret having made that choice.
I would suggest using standard gwt widgets. Simply because,
1)they are best documented,
2)they are highly customizable via css
3)from what I observe they provide the best performance
4)you dont need to learn a whole new framework built on top of another framework
but if you insist on using a framework then I suggest you take a look at this question
My advice to you is to consider your needs. Plain GWT and SmartGWT both are the best supported, so you need not look for more (unless of course both fail in what you want).
Go to their respective showcases and see what they offer and how it fits your requirements.
If gwt satisfies all your UI requirements, my advice is to choose it over SmartGWT. gwt beats SmartGWT in learning curve and documentation anytime. Also its faster(my opinion). If gwt doesn't satisfy your needs and SmartGWT does, then you should consider making the switch.
I have a year experience in smartGWT, when we started our first gwt lessons, they said use the basic gwt features and build own framework otherwise we can encounter errors which may lead to dead-ends. We considered the idea, but for the project (since we already had deadline) decided to look after some extension of gwt. We found smartGWT. The showcase was really convincing. Remember these are widgets, the basic logic of your system is still up to you.
In case if you start using smartGWT: If you don't use JSON but some normal list of java structures prepare to get hard hours/days to get use to datasources, grids, and few other components. Seriously, it had ridiculous problems (for example switching two configuration code line without reason makes work the listgrid), BUT before you drop the entire idea to use it, after a while it starts to work, and it becomes really impressive and comfortable. This is a kind of work "make it once, will work hundreds of times".
In my opinion:
don't start use smartGWT if you want to make a system which is not too complicated.
start use it if you need complicated system with lot of different features, if you don't have the time to develop everything for yourself: many components are ready in smartGWT.

GWT and Ext-GWT: comparision

What's the benefits if I am using Ext-GWT? Compare to GWT, What kind of benefits EXT-GWT could bring?
If you want your application to look like all the other Sencha applications, then go for it. Sencha comes with a set of tools and widgets that might help you make a faster start, but at the end of the day, you will need a deeper understanding anyhow, and climb that hill.
My 2 cents : go for GWT pur et dur.
for maximum flexibility
for better results
but probably a steeper start.
From the sencha site:
Sencha Ext GWT takes GWT to the next level, giving you high-performance widgets, feature-rich templates and layouts, advanced charting, data loaders and stores, and accessibility, and much more.
I was using the widgets in a project which is nice if you need something fancy not in GWT-only.
As someone who has used both extensively, I can attest to the amount of features added by GXT... ...but, at a price. Its deferred layout system is efficient, but it's a steep and sometimes frustrating learning curve, especially if you want to support IE<8.
Note that I haven't used GXT 3.0, but used 2.X for a large and successful enterprise application. If you do not write some kind of web-based unit tests (selenium recommended), you will eventually get to a point where you spend more time fixing layout bug regressions than you do creating new code.
GXT can kickstart your initial development because you can produce feature rich widget very quickly (Grid is especially nice), but when it comes time to start extending and augmenting the default widgets, you're going to hit brick walls with very little documentation.
Another big gotcha... GXT models internally serialize using a Map<String, Object>, which means that any types not explicitly serialized elsewhere in your RPC will give you errors when put in a GXT model. The workaround there is to put a private, unused field of the type you want serialized (enums were my biggest pain). Finally, gxt models are NOT default java serializable, so if you want to store them in sessions or pass them around on the server, it's not going to go well for you.
All that said, once you get the hang of GXT, and provided you don't dig too deeply into its guts, it is a great tool. The widget sets themselves are very nice...
Basically, if you intend to create a monolithic, feature rich, complex app where you need lots of control over how things are rendered, GXT will probably get in your way.
If you want to bang out a shiny app over the weekend, don't reinvent the wheel, and just use whatever works.

Is GWT still an option for a large business application [closed]

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My company is planning on developing a brand new web front-end application.
Some background:
It must "sizzle" i.e. a nice marketable look and feel.
Our development team has no Java experience, with limited experience in Silverlight, Javascript, JQuery or CSS.
Time to market is a factor.
We need to stream large amounts of data from an Oracle database.
It must support 500 - 1000 concurrent users
It will be hosted internally behind a firewall.
We need mapping (geo-spatial) capabilities.
Someone has recommended using GWT instead of Silverlight or Traditional technologies(Javascript, jquery, CSS etc.).
I am not sure if this is the right way to go? A lot of the GWT news is from 2007/2008. It makes me think that this technology is old and maybe dying.
If you had a choice would you choose GWT?
unfortunately two of your statements are mutually exclusive in this context:
Our development team has no Java experience
Time to market is a factor
I'm a Java programmer who has picked up GWT over the last year or so. It's immensely effective being able to write direct to the browser using a compiled language & mature development tools. I can fly through web-development faster than ever before (using ASP, JSP, ExtJS ...).
But, as the other commenters have said: if you've no Java experience you're going to find it a real challenge picking up both technologies (Java & GWT) in a short time. If you do manage to make it to market in a reasonable time I could only imagine the code base would be in very poor condition (since you'd be learning as you go) - which would be a very poor foundation for your organisation's shiny new venture.
There again, you don't have a 'lot' of skills in the other related skills you listed either.
I suspect there's a more effective solution. As some wise old goat project manager said:
I have three variables to delivering your project: time, cost and quality. Pick any two
In your situation, if the organisation wants a quality product in a short time, it's the cost factor that must compensate - your organisation should buy in some interim GWT expertise to give you a sound software architecture and to mentor your team for the next few months. After that you'll be ready to take the reigns, inheriting a quality codebase by 'standing on the shoulders of giants'.
As others have said, GWT definitely is not a dying project. Quite the contrary actually as there are now more than 20 regular contributors from within Google (versus a semi-dozen back in 2008). Wave (despite being discontinued as a Google service, it's still alive as an Apache Foundation project), Orkut, AdWords, Google Moderator and the new (still beta) Google Groups are made with GWT; and parts of Google Buzz and a few other projects at Google are built with it too.
Now as to your choice:
Silverlight is a dying technology. Microsoft made it clear that it now invests in "HTML5": http://www.zdnet.com/blog/microsoft/microsoft-our-strategy-with-silverlight-has-shifted/7834
GWT is mostly a client-side toolkit, but it comes with "high productivity" tools for client-server communications (GWT-RPC and RequestFactory for end-to-end protocols, AutoBeans for easy JSON serialization). With UiBinder, you can easily put to use your web designer skills.
if you're comfortable with JS, then go for it, but then you'd have to choose the "right toolkit" (jQuery? Google Closure?). Otherwise (which seems to be the case), it really depends how much "ajaxy" you need/want to be. I'm a strong believer in "one-page apps", but YMMV, or you can have specific constraints that rule it out. In any case, you'd have to choose a server-side technology.
So, depending on your needs/wants and skills, I'd choose GWT or "some JS toolkit". In any case, you'll have full control over the look and feel (unless you choose one of the bloated players: ExtJS/ExtGWT, SmartGWT or similar; you'll probably have a shorter time-to-market with these, but you'll pay it later, in terms of performance, integration with other toolkits, and look-and-feel).
In the light of what you're saying about your skills, I would definitely recommend GWT (despite your lack of experience with Java); because lack of experience with JavaScript is far worse than lack of experience with Java (you're talking about a "large application", so it's really important to start building things right and/or have tools to help refactoring, which you'll have with Java).
#ianmayo replied while I was writing the above, and I can only second what he said!
GWT is definitely not old or dying! A lot of Google's own applications are developed using GWT. You can download the GBST case study and learn how the global financial company uses GWT to improve productivity and create a rich user experience. You have to know that when you use GWT you automatically use javascript, html, etc. You create a your gwt application in java, but when you compile it gwt creates a folder with html files, javascript code, css, etc...
I definitely recommend it!
In order not to mislead readers with above seemingly unanimous answers, keep objective view in respected stackoverflow, following review expressed exact experiences I had with using GWT. Whether GWT is dying depends on how many new apps will adopt it,Google trend can tell (gwt trend).
Excerpt from https://softwareengineering.stackexchange.com/questions/38441/when-not-to-use-google-web-toolkit
>
I am both good and bad to answer this question - good, in that I've actually used it before, and bad, in that I was quite experienced with HTML/CSS/JavaScript prior to working with GWT. This left me maddened by using GWT in a way that other Java developers who don't really know DHTML may not have been.
GWT does what it says - it abstracts JavaScript and to some degree HTML into Java. To many developers, this sounds brilliant. However, we know, as Jeff Atwood puts it, all abstractions are failed abstractions (worth a read if considering GWT). With GWT, this specifically introduces the following problems:
Using HTML in GWT sucks.
As I said it, to some degree, even abstracts away HTML. It sounds good to a Java developer. But it's not. HTML is a document markup format. If you wanted to create Java objects to define a document, you would not use document markup elements. It is maddeningly verbose. It is also not controlled enough. In HTML there is essentially one way to write
<p>Hello how are <b>you</b>?</p>
In GWT, you have 3 child nodes (text, B, text) attached to a P node. You can either create the P first, or create the child nodes first. One of the child nodes might be the return result of a function. After a few months of development with many developers, trying to decipher what your HTML document looks like by tracing your GWT code is a headache-inducing process.
In the end, the team decided that maybe using HTMLPanel for all HTML was the right way to go. Now, you've lost many of GWT's advantages of having elements readily available to Java code to bind easily for data.
Using CSS in GWT sucks.
By attachment to HTML abstraction, this means that the way you have to use CSS is also different. It might have improved since I last used GWT (about 9 months ago), but at the time, CSS support was a mess. Because of the way GWT makes you create HTML, you often have levels of nodes that you didn't know were injected (any CSS dev knows how this can dramatically affect rendering). There were too many ways to embed or link CSS, resulting in a confusing mess of namespaces. On top of that you had the sprite support, which again sounds nice, but actually mutated your CSS and we had problems with it writing properties which we then had to explicitly overwrite later, or in some cases, thwarted our attempts to match our hand-coded CSS and having to just redesign it in ways that GWT didn't screw it up.
Union of problems, intersection of benefits
Any languages is going to have it's own set of problems and benefits. Whether you use it is a weighted formula based on those. When you have an abstraction, what you get is a union of all the problems, and an intersection of the benefits. JavaScript has it's problems, and is commonly derided among server-side engineers, but it also has quite a few features that are helpful for rapid web development. Think closures, syntax shorthand, ad-hoc objects, all of the stuff done by Jquery (like DOM querying by CSS selector). Now forget about using it in GWT!
Separation of concerns
We all know that as the size of a project grows, having good separation of concerns is critical. One of the most important is the separation between display and processing. GWT made this really hard. Probably not impossible, but the team I was on never came up with a good solution, and even when we thought we had, we always had one leaking into the other.
Desktop != Web
As #Berin Loritsch posted in the comments, the model or mindset GWT is built for is living applications, where a program has a living display tightly coupled with a processing engine. This sounds good because that's what so many feel the web is lacking. But there are two problems: A) The web is built on HTTP and this is inherently different. As I mentioned above, the technologies built on HTTP - HTML, CSS, even resource-loading and caching (images, etc.), have been built for that platform. B) Java developers who have been working on the web do not easily switch to this desktop-application mindset. Architecture in this world is an entirely different discipline. Flex developers would probably be more suited to GWT than Java web developers.
In conclusion...
GWT is capable of producing quick-and-dirty AJAX applications quite easily using just Java. If quick-and-dirty doesn't sound like what you want, don't use it. The company I was working for was a company that cared a lot about the end product, and it's sense of polish, both visual and interactive, to the user. For us front-end developers, this meant that we needed to control HTML, CSS, and JavaScript in ways that made using GWT like trying to play the piano with boxing gloves on
First of all , GWT is not dying technology, its usage increases, and its latest version is 2.2. I am using GWT for 2 years, since version 1.6. Its improvements since them is quite amazing.
Since GWT is client side technology, it does have only positive effects of your application scaliblity feature. Because server side web technologies such as jsf, struts, wicket are server resource consumers, but gwt does not need any server resource to render user interface..
But there is problem for your team. Because your team has no java experience, it would be quite difficult to adapt yourself two new technologies java and gwt.. If you have time to learn , I would strongly suggest GWT.
It takes approx 1 year to become proficient in GWT. Using GWT pays off if you develop an application as sophisticated as MicrosoftOffice or PhotoShop. It makes no sense to use GWT for small and relatively simple apps, IMHO. GWT is a time killing framework indeed, and you have to have very strong reasons to use it. I think that 99% of web apps don't need GWT.
GWT is not dying framework, but time killing framework. It has security issue. You can do easily CSRF(Cross site request forgery) request to the GWT applications. Also Java and Javascript are totally different languages, you can't translate easily. For your productivity avoid GWT.

Java Web Framework Prototyping tools

At the moment Iam evaluating java web frameworks. More precisely Iam talking about GWT, JSF2 and apache wicket. One very importent criteria in this evaluation is prototyping.
The prototyping process in my company can be described by the folloing:
The customer can produce GUIs with an easy to use WYSIWYG editor, by drag&drop-ing web components on the corporate predefined website structur. There is also a need for some litte dynamic being like navigation from one frame to another.
So Iam looking for tools. These tools should not only provide nice GUIs but also deliver
some basic code, which can be forwarded to the development. The aim is to avoid missunderstandings between designers and developers as much as possible. More or less the
developers just have to implements the code, but not to implement the optical requirements.
In addition it would be desirable to customize the components thats been used in the WYSIWYG editor. Does anyone know any good tools for the mentioned frameworks (GWT, JSF2, wicket)?
One of the challenges with WYSIWYG tools for UI is that you generally have to pick between rapid prototyping and maintainable code. Even then, as soon as you want to do something that's not supported by the prototyping tool, you can implement it as you would without the prototyping tool, but your round-trip functionality (namely turning your app back into something that can be edited) is broken or crippled unless extra work is done to generate the metadata that the editor needs.
Upgrading between major releases is another issue. Vendors and groups who have developed these tools have a historically spotty record of when they stop supporting older versions, reasonably because of limited resources and sometimes difficult problems with how to track solid innovation happening in the framework itself.
My suggestion instead is to prototype with an RIA prototyping tool like Balsamiq Mockups or use a grid system like 960 Grid to generate rapid prototypes, then use a web development framework that allows your developers to run the code with or without the backend server. Wicket has a tag called that is great for this kind of thing -- web devs can fill a div with stuff that a component should generate, and Wicket devs can wrap the contents of that tag with after they implement it. Both parties can coexist for a long time that way.
Try GWT Designer for GWT.
Introduction
Quick Start Guide
Download
There's nothing like this for Wicket that I know of. The closest you would get to any kind of resource reuse from your customer would be to give them a drag and drop HTML editor - the resulting HTML could then form the basis of Wicket page/panel layout.
if you are planing to use a javascript library, you may use extjs,
http://www.sencha.com/products/js/
they have developed a nice designer
www.sencha.com/products/designer/
there is also a port of ext in GWT
www.sencha.com/products/gwt/
You have to pay for a commercial license if your application isn't open source!

Which web application framework? [closed]

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From the following list of frameworks, which one would you use to develop a rich web application and why would you choose it over the others?
Sproutcore
GWT
ExtJS
GXT
SmartGWT
Dojo / Dijit
Flex
Capuccino
Grails
I'm personally tired of browser inconsistencies. If someone else has solved the problem, I'd rather not do it again. That's why I'm getting more interested in front ends like cappuccino and qooxdoo. They are a zero-HTML zero-CSS solution.
These are based on my personal experiences using the frameworks you have mentioned. So yes, it is a bit biased. So as others have said over and over again, define your requirements and which one do you think fits your requirement based on what people have suggested here.
GWT is too verbose eventhough I found many Java developers love GWT because you can unit test it and it's all in Java. But I personally don't like it because it is far from being simple. There are times when I feel I can tweak a little bit with Javascript, but with GWT I am enforced to do it with several lines of Java code.
GXT is too far from GWT these days and you will find it difficult to do things as GXT has its own way of doing things which is way too different from GWT. When complex requirement come up, in the end you are going to go back doing plain GWT. And oh, their technical support is not that good either as I had several bad experiences when asking few questions to them.
Ext-JS is good for simple stuff and the look and feel is really slick. But when things gets more complex, you are going to fight you're way through. Eventhough I have dealt with the GXT tech support, I haven't dealt with the ExtJS tech support since they have different people eventhough it's in one company, so I can't say much.
Flex is nice, really nice. But again it is good for simple stuff. Once things gets more complicated you are going to write lots of actionscript, which is less enjoyable. There are many things that is available out of the box which may be to difficult if you have to code it in Javascript, like multimedia support. And oh, if you are writing for a public website you must consider that not too many user has flash plugin on their browser.
Grails, I'm not sure how you would implement RIA apps with Grails since Grails is just another MVC framework which you need to add your own RIA framework on top of it such as the ones that you have mentioned.
This is strictly a matter of opinion. You will not get any definitive answers from anyone, since anyone that answers will have one or another that they personally prefer.
Try each one for long enough to decide which one is best for your (or your team's) purposes.
That being said, I prefer GWT. Others will invariably disagree with me.
Reasons that I like GWT:
You can share (some) client- and server-side code (as long as your server is written in Java)
GWT makes a lot of advanced performance features really easy (e.g., deferred JS loading, image spriting, CSS obfuscation)
A focus on one-page apps, with third-party support for Places (using the gwt-presenter library)
It's just as easy to add GWT to an existing web page as it is to create a full one-page GWT app
UiBinder allows you to write your UI using a declarative HTML-like syntax; you're not stuck writing Swing-like UI if you don't want to
Browser incompatibilities are (mostly) taken care of by GWT -- you just write Java code, and GWT compiles it to work on every browser
Things that may make GWT not right for you:
If your server is already written in something besides Java, you will still be able to write your UI in GWT, but you'll lose out on some nice features
Compilation time using GWT is a non-trivial cost -- Development Mode mitigates this a lot, but it's still an issue sometimes
As others have mentioned, GWT can be considered "verbose" compared to simple JavaScript libraries like jQuery or ExtJS
Ext GWT has worked well for my project. The premium support has been good.
However the project is for internal use which has allowed deployment to be restricted to one browser on one OS, and no effort has been made to change the default appearance or behaviour of Ext GWT.
Developing entirely within Java is a key benefit as it helps to keep the project manageable as features are added.
I am currently working on a grail/flex hybrid app that is working a lot better than I expected. I have looked at GWT but there were not a lot of books about it at the time and it seemed to stress the leveraging of Swing-like programming techniques which I have never liked. I agree with the comment about trying them all out. Run hello app they all have and measure how hard or easy it is to modify. Also tool (IDEs, Maven, CI...etc) support can be a big factor as well in terms of being immediately productive.
We are using Grails+ExtJS here. Since we try to make an idiomatic ExtJS application, Grails is not fully utilized, though it still makes sense to use Grails instead of, say, JSP, for the server-side part.
Why ExtJS: Because it's a very rich toolkit for GUI-like web applications. Our job is to replace an old Motif GUI, so this is exactly what we need.
Why Grails: Because it gets the job done easily and quickly. For the communication with the ExtJS part, we need a lot of JSON, and in Grails it's like that:
import foo.bar.FooBar
class FooBarController {
def viewFooBars = {
def list = FooBar.getList(session.userId, params.foo, params.bar)
def result = [resultset: list] as JSON
response.setHeader('Content-disposition', 'filename="json"')
response.contentType = "text/json";
render result
}
}
And that's even two or three lines more than necessary...
Unfortunately the answer will be opinionated, GWT in it's purest form is not an eye-candy. That being said, ExtJs GXT is super hunky dory. One of the major issues I face with evolving frameworks is that they are not absolutely defect free, If I remember correctly, GWT 2.0 was shipped out with missing CSS styles for some of the new layouts. I am trying to trouble shoot an issue in ExtJs/GXT since last 5 days :(, frameworks obfuscate a lot of things. I will go with any framework that is absolutely robust and gives appropriate error messages. I haven't worked with others though.
I'd recommend Dojo.
In addition to the massive infrastructure it provides, Dojo 1.6 is also the first (and only) popular JavaScript Library that can be successfully used with the Closure Compiler's Advanced mode, with all the size, performance and obfuscation benefits attached to it -- other than Google's own Closure Library, that is.
http://dojo-toolkit.33424.n3.nabble.com/file/n2636749/Using_the_Dojo_Toolkit_with_the_Closure_Compiler.pdf?by-user=t
In other words, a program using Dojo can be 100% obfuscated -- even the library itself.
Compiled code has exactly the same behavior as plain-text code, except that it is much smaller (average 25% over minifiers), runs much faster (especially on mobile devices), and almost impossible to reverse-engineer, even after passing through a beautifier, because the entire code base (including the library) is obfuscated.
Code that is only "minified" (e.g. YUI compressor, Uglify) can be easily reverse-engineered after passing through a beautifier.
ExtJs is great for creating complex web applications. The API provides anything you can imagine in a webapp and its really easy to extend any component after some time.
You can plug it to any backend (we use django or php) and reuse or extend any component in several different applications.
You'll need severals months to feel comfortable with it. IMHO.
That said, the lib is sometimes a bit too slow for simples uis like a website (then you can use ExtCore). But when it comes to webapps this is not an issue.
Im not a java guy so GWT was not an option for me :/
hope this helps