A sample project with multiple login page in using Spring Security.

form user resources are under /form/formHome (login with user/test), logout with /form/logout

Basic authentication user is under /basic/basicHome (login with basic_user/test) when prompted, logout with basic/logout

Since these login pages are not from different applications, they share the SecurityContextHolder or the security context. So if you login from one login page and then try to go the protected resource of the other, you won't be redirected to the next login page. Instead you'll get the 403 (depending on the roles assigned by the different login pages). At a time only one login session can be maintained.