Vaadin integration with Google App Engine

Question

i'm trying to integrate Vaadin with Google App Engine, after a number of resolved bugs and problems i've reached this exception

    EXCEPTION 
java.lang.ClassNotFoundException: com.vaadin.terminal.gwt.server.GAEApplicationServlet
    at com.google.appengine.runtime.Request.process-a03353a24bf46b73(Request.java)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:359)
    at org.mortbay.util.Loader.loadClass(Loader.java:91)
    at org.mortbay.util.Loader.loadClass(Loader.java:71)
    at org.mortbay.jetty.servlet.Holder.doStart(Holder.java:73)
    at org.mortbay.jetty.servlet.ServletHolder.doStart(ServletHolder.java:242)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
    at org.mortbay.jetty.servlet.ServletHandler.initialize(ServletHandler.java:685)
    at org.mortbay.jetty.servlet.Context.startContext(Context.java:140)
    at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1250)
    at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:517)
    at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:467)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:50)
    at com.google.tracing.TraceContext$TraceContextRunnable.runInContext(TraceContext.java:483)
    at com.google.tracing.TraceContext$TraceContextRunnable$1.run(TraceContext.java:490)
    at com.google.tracing.TraceContext.runInContext(TraceContext.java:777)
    at com.google.tracing.TraceContext$DoInTraceContext.runInContext(TraceContext.java:754)
    at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.java:345)
    at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:337)
    at com.google.tracing.TraceContext$TraceContextRunnable.run(TraceContext.java:487)
    at java.lang.Thread.run(Thread.java:722)

Which problem could it be?

Answer 1

It is definitely missing library.

Make sure, you attached Vaadin libraries to you war. They should be located in your WEB-INF/lib folder.

If you are not using maven, give it a try. You can make a GAE working project from archetype. https://vaadin.com/blog/-/blogs/66996