--- old/src/java.base/share/classes/java/lang/NullPointerException.java	2019-08-27 17:27:30.114324386 -0700
+++ new/src/java.base/share/classes/java/lang/NullPointerException.java	2019-08-27 17:27:29.866324386 -0700
@@ -51,6 +51,7 @@
  */
 public
 class NullPointerException extends RuntimeException {
+    @java.io.Serial
     private static final long serialVersionUID = 5162710183389028792L;
 
     /**