protected function buildClassificationsFromConfiguration($configuredMappedClasses) : array
    {
        $classifications = [];
        foreach ($configuredMappedClasses as $class) {
            if ( (empty($class['patterns']) && empty($class['matchPatterns'])) || empty($class['class'])) {
                throw new \InvalidArgumentException('A class configuration in SOLR_CLASSIFCATION needs to have a pattern and a class configured. Given configuration: ' . serialize($class));
            }

                // @todo deprecate patterns configuration
            $patterns = empty($class['patterns']) ? [] : GeneralUtility::trimExplode(',', $class['patterns']);
            $matchPatterns = empty($class['matchPatterns']) ? [] : GeneralUtility::trimExplode(',', $class['matchPatterns']);
            $matchPatterns = $matchPatterns + $patterns;
            $unMatchPatters = empty($class['unmatchPatterns']) ? [] : GeneralUtility::trimExplode(',', $class['unmatchPatterns']);

            $className = $class['class'];
            $classifications[] = GeneralUtility::makeInstance(
                ClassificationItem::class,
                /** @scrutinizer ignore-type */ $matchPatterns,
                /** @scrutinizer ignore-type */ $unMatchPatters,
                /** @scrutinizer ignore-type */ $className
            );
        }

        return $classifications;
    }