code: public ValidationException getException() {
          StringBuilder exceptionMessage = new StringBuilder();
          for (Problem problem : problems) {
              exceptionMessage.append(String.format("\n%s: %s", problem.getContext().getPath(), problem.getMessage()));
          }
          return new ValidationException(exceptionMessage.toString());
      }
docs: Factory method to create an exception with all problems identified in the message.
  
  @return ValidationException.