I want to test CountdownClock add-on. It is throwing java.lang.ClassNotFoundException: com.vaadin.shared.communication.ServerRpc. The CountdownClock.jar is not containing any such class. Can anyone help?

You need Vaadin 7.

I have downloaded 1.0 version of CountdownClock add-on which is compatible with 6.2+ version of vaadin. So I think it should not be related to vaadin 7. I have checked the CoundownClock.jar. This jar is not having ServerRpc class.

Yes, but Vaadin 7 has. And Vaadin 6 has not. So Vaadin 7 is required. Might be an packaging-error of the add-on.

thank you for showing the correct path. I will try to download vaadin 7 now and will run with it.