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CssImport when using Component Exporter by Mikhail Shabarov, 4 weeks ago
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Vaadin Forum4. Other

Vaadin 7.5.8 + Eclipse Mars + Google App Engine

Billy Hawkins
6 years ago Nov 05, 2015 3:58am

Hi,

I'm just starting with Vaadin and I'm trying to test it out by deploying the example project that is created by the Vaadin plug-in for Eclipse to Google App Engine. I followed the directions at https://vaadin.com/wiki/-/wiki/Main/Google%20AppEngine%20HOWTO, set up a GAE project and deployed it successfully. I'm able to see the static index page, but when I make a request to the generated servlet, I get a ClassNotFoundException for GAEVaadinServlet.

I did a search and found that someone was able to solve this issue a few years ago by going to the Java Build Path and editing the Ivy libraries to load files from "retrieved artifacts" instead of from the cache (https://vaadin.com/forum/#!/thread/2442343/2603772). This did not solve the problem for me, and I found that the JARs in my project's lib/ folder change every time I edit one of the Ivy library entries on the build path...even if I don't actually change anything. No matter what I do, Eclipse complains of at least a couple JARs missing (the exact JARs missing change every time), preventing me from being able to build the project. I checked the cache, and am able to see the "missing" JARs there.

I've never worked with Ivy before, so I'm not sure if there's something I'm doing wrong there, but I haven't made any changes to the default settings unless instructed to.

I'm very confused by the behavior I'm seeing and have no idea what I'm doing wrong. Any help is appreciated.

Billy Hawkins
6 years ago Nov 05, 2015 4:29pm

I ended up switching the Ivy entries on the Java Build Path back to using the cache, and then I noticed Eclipse was saying a few classpath entries wouldn't be exported, which corresponded to the Ivy entries. So I right-clicked them, clicked 'Quick Fix' in the context menu and said to mark them as export dependencies, and that worked. Still not sure why Eclipse/Ivy was behaving the way it was before, but it looks like I can actually deploy the sample application correctly and use it.