public function findOneByCompoundKeyFromCache($value)
    {
        if ($value === '') {
            throw new \InvalidArgumentException('$value must not be empty.', 1331319992);
        }

        if (!isset($this->cacheByCompoundKey[$value])) {
            throw new \Tx_Oelib_Exception_NotFound();
        }

        return $this->cacheByCompoundKey[$value];
    }