--- a/src/java.base/share/classes/sun/security/x509/AlgorithmId.java	Fri Jul 20 09:07:37 2018 -0700
+++ b/src/java.base/share/classes/sun/security/x509/AlgorithmId.java	Fri Jul 20 09:55:15 2018 -0700
@@ -1039,7 +1039,7 @@
      * @return the default alg, might be null if unsupported
      */
     public static String getDefaultSigAlgForKey(PrivateKey k) {
-        switch (k.getAlgorithm().toUpperCase(Locale.ROOT)) {
+        switch (k.getAlgorithm().toUpperCase(Locale.ENGLISH)) {
             case "EC":
                 return ecStrength(KeyUtil.getKeySize(k))
                     + "withECDSA";