In my GWT application,after the user login, user is forwarded to some page. From that page when the user refreshs the page, it going back to the login page. Login page is the first page is shown to the user. How can I stop the page going back to the login page? Iam using gwt-ext framework also in my application.
That is the normal behavior of a single page web application. You can prevent this by using GWT's History management.
http://code.google.com/webtoolkit/doc/latest/DevGuideCodingBasicsHistory.html
Just add a history token (e.g. #main) to the URL after login. Then register a change handler to load the correct content, if this very token is present.