public function retrieve($identifier)
    {
        try {
            return FileSystemFile::retrieveFile($identifier);
        } catch (RuntimeException $e) {
            $msg = "An error occured while retrieving a QTI FileSystemFile object.";
            throw new FileManagerException($msg, 0, $e);
        }
    }
public function retrieve($identifier)
    {
        try {
            return FileSystemFile::retrieveFile($identifier);
        } catch (RuntimeException $e) {
            $msg = "An error occured while retrieving a QTI FileSystemFile object.";
            throw new FileManagerException($msg, 0, $e);
        }
    }
public function retrieve ( $ identifier ) { try { return FileSystemFile :: retrieveFile ( $ identifier ) ; } catch ( RuntimeException $ e ) { $ msg = "An error occured while retrieving a QTI FileSystemFile object." ; throw new FileManagerException ( $ msg , 0 , $ e ) ; } }
Retrieve a FileSystemFile object from its unique identifier.

@param string identifier
@throws \qtism\common\datatypes\files\FileManagerException
@return \qtism\common\datatypes\files\FileSystemFile
Retrieve a FileSystemFile object from its unique identifier .