Say your role involves dealing with UI technologies and part of it, naturally, is deciding which technology fits your project best so you've probably came across the big debate of Flash/Flex vs. GWT.
Although the two can live happily together without stepping on each other's toes sometimes the project dictates using one exclusively.
Both technologies mentioned above have their pitfalls, but allow me to focus on GWT and hand you 2 good reasons why you should avoid it :)
The first reason is cross-browsers compatibility:
Well - that's a complete bullshit, and if you've been messing with HTML/JS/CSS long enough you know it. GWT only claims to be fully browser compatible but the reality shows different. Gecko, Trident, Webkit and other browsers engines interpreter JavaScript differently. It is a fact. There is no one standard there. Read it again - it is a fact!
GWT claims it can compile for each browser permutation, but reality shows that it's simply not working on all browsers the same way. Forget my bad experience with it - let's rely on logic and ask, can the GWT team guarantee that they have covered all aspects of JavaScript for each JS interpreter engine? All of it? Can they? Come on...
Hold on, you know what? let's say that GWT, at it's core, is browser compatible. Does anyone use GWT alone for building RIA's? I mean, the framework don't have half of the controls needed for it yet. So what do you do? You rely on 3rd parties such as Smart Client. Now, did anyone guaranteed that Smart Client is a full browser compatible? Let me help you - it's not. How about blending IE's quirks-mode into the dance? Oh, now you're dancing, mate...
So when people tell you that GWT is browser compatible, you can tell them that you will believe it when you see a full RIA application running on IE, FF, Chrome, Safari, Opera the same way.
The second reason is memory profiling (especially on IE):
While Firefox has it's amazing Firebug (got to admit it, it's pretty amazing) IE is lacking a good developer tools, at least on IE8, which doesn't have memory profiling for it's developer tool, and for a good reason, it seems, since IE is probably the worst option to run JS on, memory-wise. Modules that run smoothly on FF or Chrome, are jammed on IE, generating an embarrassingly high memory foot print. IE simply doesn't know how to decouple JS from the DOM efficiently enough, leaving objects the GC can't touch.
Now, after searching the web for different memory profiling I came up with a few solutions, but when trying them, the information was so abstract, that I couldn't pinpoint the cause for the memory leak I was experiencing.
Having GWT generate JS code under the hood keeps you wondering why the hell objects are not marked for deletion when you have no real ability to track down the reason. I hate code generators. This truly sucks ass.
So you can always remind GWT evangelists that profiling GWT memory consumption is pure hell. At least on IE.
Needless to say, but Flash and Flex do not suffer from the 2 critical problems mentioned above. Flash is truly a cross browser technology, and profiling it's memory is easy.
With that said, you will probably make your own decision, but remember what you've learned here, just in case…
:)
Cheers.
