--- a/src/java.base/share/classes/java/lang/Number.java	Thu Aug 29 18:52:30 2019 -0400
+++ b/src/java.base/share/classes/java/lang/Number.java	Thu Aug 29 16:31:34 2019 -0700
@@ -119,5 +119,6 @@
     }
 
     /** use serialVersionUID from JDK 1.0.2 for interoperability */
+    @java.io.Serial
     private static final long serialVersionUID = -8742448824652078965L;
 }