Not getting sessin value in vaadin framework
Used below :

```
private void setCurrentUsername(String username){
    VaadinService.getCurrentRequest().getWrappedSession().setAttribute("LOGGED_IN_AS_USER",username);
    userSubMenu.setText(username);
}

public static String getCurrentUsername() {
    //log.info("User:::::::::::::::::" + (String) VaadinService.getCurrentRequest().getWrappedSession().getAttribute("LOGGED_IN_AS_USER"));
    return (String) VaadinService.getCurrentRequest().getWrappedSession().getAttribute("LOGGED_IN_AS_USER");
}

```

getting value as null when flow going to other class