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

*** 31,40 ****
--- 31,41 ----
   *
   * @since 1.5
   */
  public class IllegalFormatWidthException extends IllegalFormatException {
  
+     @java.io.Serial
      private static final long serialVersionUID = 16660902L;
  
      private int w;
  
      /**