--- a/src/java.base/share/classes/sun/security/internal/spec/TlsKeyMaterialSpec.java	Thu Aug 29 10:09:27 2019 -0700
+++ b/src/java.base/share/classes/sun/security/internal/spec/TlsKeyMaterialSpec.java	Thu Aug 29 10:52:21 2019 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -45,6 +45,7 @@
 @Deprecated
 public class TlsKeyMaterialSpec implements KeySpec, SecretKey {
 
+    @java.io.Serial
     static final long serialVersionUID = 812912859129525028L;
 
     private final SecretKey clientMacKey, serverMacKey;