Flex vs GWT again

I am working on a customized web ontology editor (something like http://webprotege.stanford.edu/ which is built by GWT). My backend will be Java+Spring+Hibernate and domain models are in Java. My frontend will be something like WebProtege which requires extensive RPC call. It is quite clear that I should use GWT as I can refer to the WebProtege open source code. However, due to company policy, I shall consider Flex as well.

I understand Flex can remotely invoke Java backend methods via BlazeDS using AMF (Is there a Flex equivalent of GWT-RPC?). I have read discussion on GWT vs Flex vs ?. If I can make full decision sure I will go with GWT. GWT strengths like support right to left characters, support iPhone/iPad, smaller size, support JSON out of the box, support printing are not important considerations for my project.

Besides GWT supports Java generic, enum; domain objects can be shared with both GWT client and server; coding are more seamlessly... anyone can suggest other strong reasons that I should only go with GWT?

FYI, I have plenty of Java experience but both GWT and Flex are new to me.

Thanks.

Updated: My management has decided to go with Flex, as I have no strong reasons to stick with GWT. Visit my another post if you have s开发者_JAVA技巧uggestions about how to make GWT gains more RIA market.

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I've evaluated Flex and GWT, and for our project at least we chose to go with Flex. Using BlazeDS for the integration with Java made things VERY fast, there are many charts you can find on the internet that'll give you a hint about how much faster, and that was one of our main criteria. Even dealing directly with XML, Flex was about an order of magnitude faster than GWT when it came to getting data back and forth from client to server, and BlazeDS made it much faster. I think it boils down to Flex clients are running in the Flash VM, and GWT is running in the Javascript interpreter. If you're running in Chrome the performance might be close, I don't know, but if you aren't running Chrome I think the performance is solidly in the Flex corner. I have done JSON in Flex, there area couple of libraries to let you do that on json.org. There is also a "History" library in Flex/Actionscript that allows you to handle back button issues. All in all, they are both great solutions, if you need to support platforms that don't support Flash, then GWT is the obvious choice, but otherwise I can say we have a very successful Flex app using Java/Spring/Hibernate on the backend via BlazeDS supporting hundreds of simultaneous users with speeds that are very favorably comparable with desktop client/server application speeds.

I'll add some background here. We were charged with replacing a Windows Client/Server application with something that would be roughly comparable in performance, much more configurable, have no configuration on the desktop, and be a "web application". We kicked around Java applets, .Net 1 click installs, GWT, and Flex. Based on a balance of ease of use, performance, the fact that we have other reasons to require Flash on our users desktops, and frankly political reasons, (java haters ;) we chose a modular Flex application. Now more than a year later, and 90+ dynamically configured modules based on user roles, I think it was pretty successful.

But, of course, YMMV ;)

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I had a chance to use both. Personally I found it difficult to customize the GWT build-in component compare to Flex. I could be wrong because I didn't create any customized GWT component while I used GWT.

On the other hand creating custom component in Flex is considerably easy. GWT MVP 2.0 supports browser history handling in easy way, so you can use the browser forward and backward button to navigate your visited pages which is not available in Flex.

When I use Spring Roo to generate the GWT as well as Flex clients. The code for GWT is much more verbose than Flex counterpart and difficult to modified and extends.

With Flex and Spring Roo for the server side, I can spend more time to decorate the UI. There are more choices for client-side framework to organize the code in Flex such as Mate, Parsely etc. Don't get me wrong, GWT MVP is also a good framework.

It's up to you to decide.