java.lang.NoClassDefFoundError: com/vaadin/data/Property$ConversionExceptio

I have this issue when i am using sql container addon with vaadin 7

NoClassDefFoundError means that the Java class loader can’t find a class with that name. Any number of things could be wrong, but most likely something has failed to load (check your classpath) or there’s a typo (source code does not match database contents). I can’t even see the full error message, since you put that as the subject and the subject got truncated by the forum software.

Post a complete error log and relevant bits of source code for futher help - without those, nobody will have any chance of being able to help you.

SQLContainer is built into Vaadin 7 so you shouldn’t use the add-on. The add-on is for Vaadin 6 and is not compatible with Vaadin 7.

Otherwise, Patrik’s comments apply.