src/java.base/share/classes/java/io/NotActiveException.java

@@ -31,10 +31,11 @@
  * @author  unascribed
  * @since   1.1
  */
 public class NotActiveException extends ObjectStreamException {
 
+    @java.io.Serial
     private static final long serialVersionUID = -3893467273049808895L;
 
     /**
      * Constructor to create a new NotActiveException with the reason given.
      *