--- a/src/java.base/share/classes/java/security/PermissionCollection.java	Thu Aug 29 10:09:27 2019 -0700
+++ b/src/java.base/share/classes/java/security/PermissionCollection.java	Thu Aug 29 10:52:21 2019 -0700
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1997, 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
@@ -96,6 +96,7 @@
 
 public abstract class PermissionCollection implements java.io.Serializable {
 
+    @java.io.Serial
     private static final long serialVersionUID = -6727011328946861783L;
 
     // when set, add will throw an exception.