TYPO3: Generic getInstance instead of makeInstance

<?php
namespace NAMESPACE\YourExtension\Utility;

/**
 * Utility: External Objects through object manager
 */
class ObjectUtility
{

    /**
     * Create instance when no object manager initiated
     *
     * @param string $class
     * @return object given class
     */
    static public function getInstance($class)
    {
        static $objectManager;
        if (!($objectManager instanceof \TYPO3\CMS\Extbase\Object\ObjectManager)) {
            $objectManager = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance('TYPO3\\CMS\\Extbase\\Object\\ObjectManager');
        }

        if ($objectManager instanceof \TYPO3\CMS\Extbase\Object\ObjectManager) {
            return $objectManager->get($class);
        }
        return null;
    }

}