Numerous exceptions on application startup.

Heyho community,

I have a vaadin application running on a JBoss AS 7.1.0. When I open the web page for the first time in any browser I get a huge amount of exceptions thrown.
Mostly they deal with the GWT toolkit. A short excerpt looks like this:

Caused by: java.lang.ClassNotFoundException: com.vaadin.terminal.gwt.client.ui.VOrderedLayout from [Module "deployment.FTWebClient.war:main" from Service Module Loader]
	at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:190)
	at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:468)
	at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:456)
	at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:398)
	at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:120)
	... 53 more

09:07:32,292 WARN  [org.jboss.modules] (http--192.168.27.29-8080-1) Failed to define class com.vaadin.terminal.gwt.client.ui.layout.CellBasedLayout in Module "deployment.FTWebClient.war:main" from Service Module Loader: java.lang.LinkageError: Failed to link com/vaadin/terminal/gwt/client/ui/layout/CellBasedLayout (Module "deployment.FTWebClient.war:main" from Service Module Loader)
	at org.jboss.modules.ModuleClassLoader.defineClass(ModuleClassLoader.java:396)
	at org.jboss.modules.ModuleClassLoader.loadClassLocal(ModuleClassLoader.java:243)
	at org.jboss.modules.ModuleClassLoader$1.loadClassLocal(ModuleClassLoader.java:73)
	at org.jboss.modules.Module.loadModuleClass(Module.java:517)
	at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:182)
        ...
Caused by: java.lang.NoClassDefFoundError: com/google/gwt/user/client/ui/ComplexPanel
	at java.lang.ClassLoader.defineClass1(Native Method) [rt.jar:1.7.0_03]
	at java.lang.ClassLoader.defineClass(ClassLoader.java:791) [rt.jar:1.7.0_03]
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) [rt.jar:1.7.0_03]
	at org.jboss.modules.ModuleClassLoader.doDefineOrLoadClass(ModuleClassLoader.java:327)
	at org.jboss.modules.ModuleClassLoader.defineClass(ModuleClassLoader.java:391)
	... 76 more
Caused by: java.lang.ClassNotFoundException: com.google.gwt.user.client.ui.ComplexPanel from [Module "deployment.FTWebClient.war:main" from Service Module Loader]
	at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:190)
	at org.jboss.modules.ConcurrentClassLoader.performLoadClassUnchecked(ConcurrentClassLoader.java:468)
	at org.jboss.modules.ConcurrentClassLoader.performLoadClassChecked(ConcurrentClassLoader.java:456)
	at org.jboss.modules.ConcurrentClassLoader.performLoadClass(ConcurrentClassLoader.java:398)
	at org.jboss.modules.ConcurrentClassLoader.loadClass(ConcurrentClassLoader.java:120)
	... 81 more

09:07:32,417 WARN  [org.jboss.modules] (http--192.168.27.29-8080-1) Failed to define class com.vaadin.terminal.gwt.client.ui.VOrderedLayout in Module "deployment.FTWebClient.war:main" from Service Module Loader: java.lang.LinkageError: Failed to link com/vaadin/terminal/gwt/client/ui/VOrderedLayout (Module "deployment.FTWebClient.war:main" from Service Module Loader)
	at org.jboss.modules.ModuleClassLoader.defineClass(ModuleClassLoader.java:396)
	at org.jboss.modules.ModuleClassLoader.loadClassLocal(ModuleClassLoader.java:243)
	at org.jboss.modules.ModuleClassLoader$1.loadClassLocal(ModuleClassLoader.java:73)
	at org.jboss.modules.Module.loadModuleClass(Module.java:517)
	at org.jboss.modules.ModuleClassLoader.findClass(ModuleClassLoader.java:182)
        ...

My application itself runs without any problems as soon as it is loaded. Do I need to install any GWT toolkit stuff on the application server?

Any help is highly appreciated.

Regards,

René

Short story: JBoss AS 7 has a broken classloader which logs errors even though the Vaadin code catches the exceptions. Including gwt-user.jar on the classpath is known to help in some circumstances. There should be an official workaround for Vaadin 6.8 (#8447) and the problem should be completely circumvented in Vaadin 7 (#8440).

Long story: http://dev.vaadin.com/ticket/7822.

Heyho Leif,

thanks for the quick response. I'm looking forward to Vaadin 6.8/7.0.

Regards,

René