--- a/src/java.base/share/classes/sun/security/ssl/CertificateMessage.java	Thu Dec 13 16:14:07 2018 +0100
+++ b/src/java.base/share/classes/sun/security/ssl/CertificateMessage.java	Thu Dec 13 15:31:05 2018 +0100
@@ -440,7 +440,7 @@
                 // It is not necessary to check the certificate update if
                 // endpoint identification is enabled.
                 String identityAlg = chc.sslConfig.identificationProtocol;
-                if ((identityAlg == null || identityAlg.length() == 0) &&
+                if ((identityAlg == null || identityAlg.isEmpty()) &&
                         !isIdentityEquivalent(x509Certs[0],
                                 chc.reservedServerCerts[0])) {
                     chc.conContext.fatal(Alert.BAD_CERTIFICATE,