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

@@ -45,10 +45,11 @@
  * @author  unascribed
  * @since   1.1
  */
 public class OptionalDataException extends ObjectStreamException {
 
+    @java.io.Serial
     private static final long serialVersionUID = -8011121865681257820L;
 
     /*
      * Create an <code>OptionalDataException</code> with a length.
      */