Javadoc
This combined LDAP authentication method supersedes both the 'LDAPAuthentication'
and the 'LDAPHierarchicalAuthentication' methods. It's capable of both:
- authenticaton against a flat LDAP tree where all users are in the same unit
(if search.user or search.password is not set)
- authentication against structured hierarchical LDAP trees of users.
An initial bind is required using a user name and password in order to
search the tree and find the DN of the user. A second bind is then required to
check the credentials of the user by binding directly to their DN.