GWT and Jetty - HTTP method GET is not supported by this URL

Answer 1

RemoteServiceServlet is designed to be used with GWTRPC. This means, that you don't implement doPost or doGet at all (doPost is even final in AbstractRemoteServiceServlet). You implement your own service methods instead, which you specify in your RemoteService interface.

If you want to implement doPost/doGet yourself, instead of using GWTRPC (see "Making HTTP Requests" in the GWT documentation), then extend the usual HttpServlet instead of RemoteServiceServlet. If you need both, I would suggest to create two separate servlets.