config/src/main/java/org/springframework/security/config/annotation/authentication/configurers/ldap/LdapAuthenticationProviderConfigurer.java
private LdapAuthenticator createLdapAuthenticator(
			BaseLdapPathContextSource contextSource) {
		AbstractLdapAuthenticator ldapAuthenticator = passwordEncoder == null ? createBindAuthenticator(contextSource)
				: createPasswordCompareAuthenticator(contextSource);
		LdapUserSearch userSearch = createUserSearch();
		if (userSearch != null) {
			ldapAuthenticator.setUserSearch(userSearch);
		}
		if (userDnPatterns != null && userDnPatterns.length > 0) {
			ldapAuthenticator.setUserDnPatterns(userDnPatterns);
		}
		return postProcess(ldapAuthenticator);
	}
private LdapAuthenticator createLdapAuthenticator(
			BaseLdapPathContextSource contextSource) {
		AbstractLdapAuthenticator ldapAuthenticator = passwordEncoder == null ? createBindAuthenticator(contextSource)
				: createPasswordCompareAuthenticator(contextSource);
		LdapUserSearch userSearch = createUserSearch();
		if (userSearch != null) {
			ldapAuthenticator.setUserSearch(userSearch);
		}
		if (userDnPatterns != null && userDnPatterns.length > 0) {
			ldapAuthenticator.setUserDnPatterns(userDnPatterns);
		}
		return postProcess(ldapAuthenticator);
	}
Creates the {@link LdapAuthenticator} to use

@param contextSource the {@link BaseLdapPathContextSource} to use
@return the {@link LdapAuthenticator} to use