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

@@ -34,10 +34,11 @@
  *
  * @since 1.5
  */
 public class FormatterClosedException extends IllegalStateException {
 
+    @java.io.Serial
     private static final long serialVersionUID = 18111216L;
 
     /**
      * Constructs an instance of this class.
      */