request.getSession(true) - returns session = null

My code:

@Theme("valo")
public class DashboardApplication extends UI {
   @Override
   public void init(VaadinRequest request) {
      final HttpServletRequest req = ((VaadinServletRequest) VaadinService.getCurrent().getCurrentRequest()).getHttpServletRequest();
      final HttpServletResponse res = ((VaadinServletResponse) VaadinService.getCurrentResponse()).getHttpServletResponse();
      ...
HttpSession session = req.getSession(true);
ClientContext context = new ClientContext();
session.setAttribute(CommonConst.CLIENT_CONTEXT, context);

here session = null.
if debug my app by putting breakpoint on line (8)  - all ok! why?

thanks

Maybe you are using a broken Servlet container (webserver)?

All good here, using Vaadin 7.6.8 and Tomcat v8.0 running on OSX 10.11.6.
Even when not debugging.

Best,
Enver
 

No! Its bug vaadin. i found.

Would you be so kind and elaborate?

Or even better, report the bug at

dev.vaadin.com ?

Thanks,
Enver