Web applications of today are often required to be quite complex – AJAX offers lots of nifty ways of giving the user a great experience. But developing stable applications using lots of JavaScript code can be quite challenging. Even though there’s help from great libraries such as Prototype, YUI and jQuery, it’s tricky to keep the code bullet-proof and fully tested.
Also, it can be difficult maintaining a decent architecture as the application grows, i.e. how to implement an MVC solution.
There’s of course a few people out there trying to address these issue, one of which being Google Web Toolkit (GWT).
We’ve discussed GWT from time to time, but haven’t really made a true effort of delving into it. I decided to try to find out how it really works and if it’s something for us to use in our applications.
Do we really need it?
I guess the first question you need to ask yourself is if you really need anything like GWT. Is our goal to build a full-feathered AJAX site without any browser reloading of pages? Do we want something with features like Gmail (from dialogues to rich-text editors)?
After researching GWT for a while, my feeling is that you either fully implement it (with effects on server-side and all) or you stick to using “old, self-developed” Javascript code. If you’re to have any kind of client-server communication (which you are), you’ll probably have to make some adjustments on the server-side as well.
Anyway… I tested a sample implementation usin GWT and as a Java fan, I was of course enjoying writing nice, strict Java code with full IDE support instead of regular JavaScript. There was really nothing to complain about when it comes to writing GWT code and it was fairly easy to get started and the compilation was quick enough and provided a nice debugging tool.
Are there any limitations?
My main concern is that using GWT will come with some limitations:
- What if I don’t what to write the code exactly like it’s done with GWT? Will I have to write all my code using GWT?
- How painful is it really to mix “regular” Javascript with GWT code (they offer a way of doing it, but it doesn’t seem like something you’d really want to do)?
- Is it really stable enough for an entire application/game? To be honest, the GWT site itself is actually quite buggy…
One nice feature that comes with GWT is the support for creating modules. It seems quite easy to create a smaller module (perhaps a text-editor) and plug it in to your application. I’d say that doing so would be a first good test of GWT, as it still feels a bit scary to rely on it for an entire application (i.e. creating entire pages, browser history states etc).
Maybe using it for smaller modules the best use of GWT in our case? It would be really nice if server-developers (Java guys) could implement advanced client-side features without being afraid to mess it all up… 
To sum it up…
I guess these questions never will be answered unless I/we actually try it out in a real implementation (or at least a real-enough prototype). There’s obviously a whole lot of things with GWT that is really nice, but I wouldn’t feel fully comfortable relying on it as of today. Trying it out in a module or two would probably be the best way to draw some real conclusions.
In the end, it’s all about what you and your product really need.
References
GWT in Practice – Ebook (lots of reading)
Ext GWT Library (great widgets)
Third-party JavaScript frameworks can be used by creating interfaces via GWT-API-Interop (http://code.google.com/p/gwt-api-interop/).
There’s a few community projects going on where others have already created these interfaces, so it should be OK to use jQuery or PrototypeJS for example.
But using the JSNI component (i.e. using native Javascript from within the Java code) is potentially very dangerous, in terms of reliable code.
[...] it Development, JavaScript Monday, January 11th, 2010 @ 11:26 | Follow comments A while back, I tried out Google Web Toolkit to see if it was any interesting. My main concerns after that early glance was the stability of the [...]