--- old/src/java.base/share/classes/java/net/UnknownServiceException.java	2019-08-27 17:28:07.410324386 -0700
+++ new/src/java.base/share/classes/java/net/UnknownServiceException.java	2019-08-27 17:28:07.218324386 -0700
@@ -37,6 +37,7 @@
  * @since   1.0
  */
 public class UnknownServiceException extends IOException {
+    @java.io.Serial
     private static final long serialVersionUID = -4169033248853639508L;
 
     /**