UserOptionController::getInstance

static function getInstance(int $userId, int $projectId): UserOptionController
{
	if (
		!array_key_exists($userId, static::$instances)
		|| !is_array(static::$instances[$userId])
		|| !array_key_exists($projectId, static::$instances[$userId])
	)
	{
		static::$instances[$userId][$projectId] = new self($userId, $projectId);
	}

	return static::$instances[$userId][$projectId];
}