public function getMigrationVersion($version)
    {
        if ($this->isVersionAvailable($version)) {
            if ($this->isVersionLoaded($version)) {
                $configuration = $this->loadedVersions[$version];
            } else {
                $configuration = $this->loadConfiguration($version);
                $this->loadedVersions[$version] = $configuration;
            }
            return $configuration;
        }
        throw new MigrationException('Specified version is not available.', 1345821746);
    }