security - what do when a login fails?

[Vijay Prabhakar <Vi...@eoncompany.com>]

I was looking at the JDBCRealm class provided with Tomcat 3.2.1.  I
noticed that it has a boolean authenticate() method that returns true
when a username and password pair are valid.  But when that method
returns false, the int authenticate() method returns skips setting the
remote user but still returns 0.  How do you redirect someone to a login
page using this method?  What happens here - does tomcat just check to
see if the remote user has been set and if not, it assumes that the
login failed?
 

-Vijay