/**
  * Checks if the input parameter are correct and load the parsed classes if needed
  *
  * @param mixed $arg
  * @param string $custom_list_path
  */
 private static function checkInputArgs($arg, CodeGenerator $codeGenerator)
 {
     $custom_path = $codeGenerator->getPathToClassesMethodsList();
     self::$returnValuesManager = $arg instanceof ReturnValuesManager ? $arg : new ReturnValuesManager($arg, $custom_path);
     self::$className = self::$returnValuesManager->getClassName();
     self::$extends = self::$returnValuesManager->getExtends();
     self::$implements = self::$returnValuesManager->getImplements();
     self::$classesMethods = !is_null($custom_path) ? require $custom_path : array();
 }