LdapTemplate ldapTemplate = new LdapTemplate(getInitialDirContextFactory());
while (dns.hasNext() && (user == null)) {
final String userDn = (String) dns.next();
if (ldapTemplate.nameExists(userDn)) {
LdapUserDetailsImpl.Essence userEssence = (LdapUserDetailsImpl.Essence)
ldapTemplate.retrieveEntry(userDn, getUserDetailsMapper(), getUserAttributes());
userEssence.setUsername(username);
user = userEssence.createUserDetails();
}