code: public int getInt(String key) {
      String value = getString(key);
      if (StringUtils.isNotEmpty(value)) {
        return Integer.parseInt(value);
      }
      return 0;
    }
docs: Effective value as {@code int}.
  @return the value as {@code int}. If the property does not have value nor default value, then {@code 0} is returned.
  @throws NumberFormatException if value is not empty and is not a parsable integer