code: public static FormValidation validateArtifactoryCombinationFilter(String value)
              throws IOException, InterruptedException {
          String url = Util.fixEmptyAndTrim(value);
          if (url == null)
              return FormValidation.error("Mandatory field - You don`t have any deploy matches");
  
          return FormValidation.ok();
      }
docs: Validate the Combination filter field in Multi configuration jobs