private LdapAuthoritiesPopulator getLdapAuthoritiesPopulator() {
		if (ldapAuthoritiesPopulator != null) {
			return ldapAuthoritiesPopulator;
		}

		DefaultLdapAuthoritiesPopulator defaultAuthoritiesPopulator = new DefaultLdapAuthoritiesPopulator(
				contextSource, groupSearchBase);
		defaultAuthoritiesPopulator.setGroupRoleAttribute(groupRoleAttribute);
		defaultAuthoritiesPopulator.setGroupSearchFilter(groupSearchFilter);
		defaultAuthoritiesPopulator.setRolePrefix(this.rolePrefix);

		this.ldapAuthoritiesPopulator = defaultAuthoritiesPopulator;
		return defaultAuthoritiesPopulator;
	}