Server side equivalent of Window.Location.getParameter() in GWT

On the client side I am able to retrieve URL parameters in GWT by

String parameterName = Window.Location.getParameter("parameterName");

Doing the same server side however gives me this exeption:

[...]
threw an unexpected exception: java.lang.ExceptionInInitializerError
[...]
Caused by: java.lang.ExceptionInInitializerError
at com.google.gwt.user.client.Window$Location.getQueryString(Window.java:262)
at com.g开发者_开发百科oogle.gwt.user.client.Window$Location.ensureParameterMap(Window.java:321)
at com.google.gwt.user.client.Window$Location.getParameter(Window.java:211)
at com.icada.idea.server.CurrentUser.getUser(CurrentUser.java:31)

Where line 31 in CurrentUser reads:

String noLogin= Window.Location.getParameter("nologin");

So how do I get the URL parameter server side? Or is it the only way to pass as a parameter to the method I am calling?

On the server side, you don't have a Window. All you get from the client is a request - and that request may contain parameters (GET parameters or POST parameters).

You can retrieve them by using

request.getParameter("parameterName");

The request is available in Servlets, e.g. in the doGet(HttpServletRequest request, HttpServletResponse response) and doPost(HttpServletRequest request, HttpServletResponse response) methods.

If you're using GWTRPC, you could use getThreadLocalRequest(), but as you usually don't post the Window's parameters as POST parameters with a GWTRPC call, it would be more natural to pass the parameters you require as method parameters.