using request builder to authenticate user: Not working in spring security - authentication

Question

I need to authenticate a user in a page based on the remember me cookie,
inspired by this site: Tutorial for checking spring authentication,
I came up with a solution for checking the authentication.
Changes made in my application
applicationContext-security.xml:
<intercept-url pattern='/**AuthenticationChecker.html' access="ROLE_ADMIN"/>
...
<form-login login-page="/Login.html" authentication-failure-url="/Login.html" always-use-default-target="true" default-target-url="/Main.html"/>
Gwt code:
try
{
RequestBuilder rb = new RequestBuilder(
RequestBuilder.POST, "AuthenticationChecker.html");
rb.sendRequest(null, new RequestCallback()
{
public void onError(Request request, Throwable exception)
{
RootPanel.get().add(new HTML("[error]" + exception.getMessage()));
}
public void onResponseReceived(Request request, Response response)
{
RootPanel.get()
.add(new HTML("[success (" + response.getStatusCode() + "," + response.getStatusText() + ")]"));
}
}
);
}
catch (Exception e)
{
RootPanel.get().add(new HTML("Error sending request " + e.getMessage()));
}
AuthenticationChecker.html is a simple blank html page,
from what I understand, as AuthenticationChecker.html requires role as admin, I should have got a 401 Unauthorized if remember me cookie was not present and a 200 OK if the user was authenticated and his cookie was present.
However, the output always shows: [success (200,OK)]
To cross check, i simply typed authenticaionChecker.html (without logging in) and it returned back to Login.html indicating that spring is indeed authenticating the user.
Am I doing something wrong here ?

Answer 1

If you look at the tutorial, you'll see that a 401 is only returned when you're using Basic Authentication. With form-based authentication, you have to check the response text for an error message. For example:
public void onResponseReceived(Request request, Response response) {
if (response.getStatusCode() != Response.SC_OK) {
onError(request, new RequestException(response.getStatusText() + ":\n" + response.getText()));
return;
}
if (response.getText().contains("Access Denied")) {
Window.alert("You have entered an incorrect username or password. Please try again.");
} else {
// authentication worked, show a fancy dashboard screen
}
}