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

@@ -33,10 +33,11 @@
  *
  * @since 1.5
  */
 public class IllegalFormatException extends IllegalArgumentException {
 
+    @java.io.Serial
     private static final long serialVersionUID = 18830826L;
 
     // package-private to prevent explicit instantiation
     IllegalFormatException() { }
 }