public function getClassAliasName($className)
    {
        /*
         * Sanitize input: class names in namespaces should not, but may include a leading backslash
         */
        $className = ltrim($className, '\\');
        $classAlias = array_search($className, $this->classMap);

        if ($classAlias === false) {
            $classAlias = null;
        }

        return $classAlias;
    }