J2EE Security roles

[Venkat Reddy Valluri]

Hi, 
   I am using   catalina-4.0.4 and Form based authentication with  JDBCRealm.
   I would like to get the roles of a user from  session object in which I 
think        roles must have been stored by j2ee secuirity realm when user is 
authenticated  
   Can you please let me know  thru which session attribute I can access roles
   
Thanks in advance,
--Venkat