docs: private static Field getField(final Class cls, final String fieldName, boolean declared) {
  		$.checkNotEmpty(fieldName);
  		List<Field> fields = getFieldsList(cls, declared);
  		for (int i = 0; i < fields.size(); i++) {
  			if (fieldName.equals(fields.get(i).getName())) {
  				return fields.get(i);
  			}
  		}
  		return null;
  	}