code: public static final RuntimeException convertException(Exception ex) {
          if (ex instanceof RuntimeException) {
              return (RuntimeException) ex;
          }
          return new ExceptionConverter(ex);
      }
docs: Convert an Exception into an unchecked exception. Return the exception if it is
  already an unchecked exception or return an ExceptionConverter wrapper otherwise
  
  @param ex the exception to convert
  @return an unchecked exception
  @since 2.1.6