/**
* Gets the extension of the file.
*
* @return string
*/
public function getExtension()
{
if (is_null($this->extension) === true) {
$filename = parent::getFilename();
$str = new StringWrapper($filename);
$this->extension = $str->getFirstEndMatch($this->predefinedExtensions);
$this->hasPredefinedExt = true;
if ($this->extension === '') {
$this->hasPredefinedExt = false;
$this->extension = parent::getExtension();
}
}
return $this->extension;
}
