Vaadin EntityManager Problem

Vaadin 6 / 7 / 8 Framework Data Binding
1

Hi,

I am using EntityManager in Vaadin to access database.

But i am facing problem while creating entitymanagerconnection.

I have got the following error…

java.lang.NoClassDefFoundError: javax/persistence/EntityManager.

The question may be silly, but i cannot come out of it.

Can anybody please provide me a solution??

Thanks in advance,
Rakesh.

2

You have class path problem , Most likely you are running your application in a non JavaEE container ( you can still access JPA (java persistence API) etc but you you need to deploy all the needed libraries for one of the JPA implementations ( Hibernate, OpenJPA , EclipseLink etc… )