Welcome to the Ranch, Saritha!
If you're looking for a cookbook answer, we're not the place to look. And since we're not paid to do this, "urgent" isn't something
you should expect here either. Our primary purpose is to help people learn in an environment where they can feel comfortable and not get flamed or called stupid.
When using Active Directory for authentication the main thing to keep in mind is that unlike other LDAP servers, Active Directory has special entries that describe Windows-specific user properties and so the LDAP search rules have to be set up to use those properties instead of the more general ones you may see in non-AD LDAP examples. Do an Internet search for "Windows Active Directory LDAP authentication" and you should find some specifics.
One thing to note, though. If all application users are going to be local Windows users operating under their own identifies, you can bypass the whole LDAP thing and use basic NTLM single-signon authentication so that a user never actually has to login to the app itself, since they logged into Windows already. In the case of the
Tomcat webapp server, for example, there's a custom security Realm module you can use. Actually more than one, I think. The original one was called CAS.