src/java.base/share/classes/sun/net/ftp/FtpLoginException.java

*** 32,41 ****
--- 32,42 ----
   * FTP login operation.
   *
   * @author      Jonathan Payne
   */
  public class FtpLoginException extends IOException {
+     @java.io.Serial
      private static final long serialVersionUID = 2218162403237941536L;
  
      public FtpLoginException(String s) {
          super(s);
      }