Friday, June 24, 2016

Re: How to debug GWT application on Eclipse

"Classic" Dev Mode (or, as most people call it, "legacy" devmode) is deprecated and scheduled for deletion after the 2.8 release. It only works in Internet Explorer (not Edge, but works in IE11), and in really old versions of Firefox and Chrome/Chromium.
The way forward is "Super Dev Mode", where your application is compiled to JS on-demand, on-the-fly. This however means that you need to use JavaScript debugging tools, but thanks to SourceMaps you can see your original Java code when debugging. Those tools include your browsers' dev tools, the Eclipse SDBG plugin (only works with Chrome AFAICT), and IntelliJ IDEA built-in support (IIRC, requires a browser extension, but works in both Chrome and Firefox).

On Friday, June 24, 2016 at 10:46:52 AM UTC+2, Pierre Mineaud wrote:
Hi GWT community. 
I am trying GWT since yesterday, and I'm following the first app tutorial on gwt official.
I'm at the debugging section and i can't figure it out to debug my code in eclipse. 

I followed each line of this tutorial, so this is what I've done : 
- Installed the last eclipse version (Version: Neon Release (4.6.0))
- Installed GWT pluggin for eclipse + sdk : Plugin for Eclipse 4.5 (Mars)
- Created the first app Stockwatcher from the eclipse pluggin (I didn't used webAppCreator or maven atm)
- Built my UI code

Until there, all is working fine. I use the run as Web Application (GWT Super Dev Mode) in eclipse and I see my app working in chrome at the

The problem I have now during the debugging part is, when I put some breakpoint in my code, I relaunched my app in the same mode (GWT Super Dev Mode) but my code never stopped on my breakpoint. So I tried to launch it with Debug as Web Application (GWT Super Dev Mode)... Same here : No stop on breakpoint. So I tried an other mode : Run/Debug as Web Application (GWT Classic Dev Mode), my generated url changed to But when I launched it in my chrome / FF, I got this popup : "Couldn't load stockwatcher from Supder Dev Mode server at Please make sure this server is ready. Do you want to try again?"

What I did wrong ?

Thanks for your tips ;)

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