How do I authenticate against LDAP but load user roles from a database?
The LdapAuthenticationProvider bean (which handles normal LDAP authentication in Spring Security) is configured with two separate strategy interfaces, one which performs the authenticatation and one which loads the user authorities, called LdapAuthenticator and LdapAuthoritiesPopulator respectively. The DefaultLdapAuthoitiesPopulator loads the user authorities from the LDAP directory and has various configuration parameters to allow you to specify how these should be retrieved.
