--- old/src/java.base/share/classes/java/net/MalformedURLException.java	2019-08-27 17:27:59.786324386 -0700
+++ new/src/java.base/share/classes/java/net/MalformedURLException.java	2019-08-27 17:27:59.622324386 -0700
@@ -36,6 +36,7 @@
  * @since   1.0
  */
 public class MalformedURLException extends IOException {
+    @java.io.Serial
     private static final long serialVersionUID = -182787522200415866L;
 
     /**