--- a/src/java.base/share/classes/javax/security/auth/PrivateCredentialPermission.java	Thu Dec 13 16:14:07 2018 +0100
+++ b/src/java.base/share/classes/javax/security/auth/PrivateCredentialPermission.java	Thu Dec 13 15:31:05 2018 +0100
@@ -312,7 +312,7 @@
 
     private void init(String name) {
 
-        if (name == null || name.trim().length() == 0) {
+        if (name == null || name.trim().isEmpty()) {
             throw new IllegalArgumentException("invalid empty name");
         }