How to access HttpServletRequest from vaadin UI class in vaadin 8

Question

In our vaadin 6 application, we can access the HttpServletRequest object from onRequestStart method from our vaadin Application sub-class. We need to access the HttpServletRequest to obtain parameters passed by the caller which starts our vaadin application (an HTML Form). Now we are converting the application to vaadin 8. I was not able to find a method in vaadin UI similar to onRequestStart that exposes the raw HttpServletRequest that starts the vaadin application. I tried to use getParameter method of the VaadinRequest object passed to UI's init method, however, this could not retrieve the parameters passed. How can I get the parameters in the raw HttpServletRequest in vaadin 8?

Answer 1

I'm surprised that they can not be retrieved through getParameter(...).

Since you're running on a servlet, the VaadinRequest will be a VaadinServletRequest. After casting it to this subclass, you can use getHttpServletRequest() to get the wrapped request.