Use with subtypes

A service can also be requested for not just a type, but a subtype too:

// Find a service for a file type
if (is_object($serviceObject = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstanceService('metaExtract', $fileType))) {
        $serviceObj->setInputFile($absFile, $fileType);
        if ($serviceObj->process('', '', array('meta' => $meta)) > 0 && (is_array($svmeta = $serviceObj->getOutput()))) {
                $meta = $svmeta;

In this example a service type "metaExtract" is requested for a specific subtype corresponding to some file's type. With the returned instance, it then proceeds to retrieving whatever possible meta data from the file.

If several services are available for the same subtype, the one with the highest priority (or quality if priority are equals) will be used.