NoClassDefFoundError on SubscriberExceptionHandler?

Attempting to implement the same sort of “Event” and “EventBus” stuff that’s in the Dashboard demo, I’m getting this error when I try to run the app:

Vaadin is running in DEBUG MODE.
Add productionMode=true to web.xml to disable debug features.
To show debug window, add ?debug to your application URL.
Aug 31, 2015 3:06:08 PM com.vaadin.server.DefaultErrorHandler doDefault
java.lang.NoClassDefFoundError: com/google/common/eventbus/SubscriberExceptionHandler
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(
    at org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(
    at org.apache.catalina.loader.WebappClassLoaderBase.findClass(
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(

Line 48 in “” is:

private final SchedulingEventBus schedulingEventbus = new SchedulingEventBus();

(I’ve mostly just replaced all the “Dashboard” references to “Scheduling” to conform with my web app.) Of course, it doesn’t help that I am still trying to figure out the point of “” and “” and how they work. (Still a newbie.)

Finally got an answer to this over on
. Turns out I need to add Google’s Guava package (or whatever it’s called) to my ivy.xml file, thusly:

<dependency org="" name="guava" rev="18.0"/>

This allows the (presumably latest) guava components needed for the SchedulingEventBus to be downloaded and installed.