src/java.base/share/classes/java/util/EventObject.java

*** 36,45 ****
--- 36,46 ----
   * @since 1.1
   */
  
  public class EventObject implements java.io.Serializable {
  
+     @java.io.Serial
      private static final long serialVersionUID = 5516075349620653480L;
  
      /**
       * The object on which the Event initially occurred.
       */