We are building an intranet site, where we want to authenticate the user on the basis of his windows login, instead of providing him a login page. This will help the users to remember their password easily. How this can be achieved thru java.
You can retrieve the user name using getProperty("user.name"), but I'm sure you'll have to resort to JNI for the password. Or more likely, you will have to hash a String and compare that to the stored password.
Unforunately is far more complicated than that. You should have a look at Samba NTLM authentication or Taglish SSPI JAAS provider. And (unless you already know about these) read up on NTML and JAAS.