/**
  * Returns true, if the specified file shall be displayed inline in the browser.
  */
 public static function _isFileInline($a_file_name)
 {
     if (self::$_inlineFileExtensionsArray === null) {
         require_once 'Services/Administration/classes/class.ilSetting.php';
         $settings = new ilSetting('file_access');
         self::$_inlineFileExtensionsArray = preg_split('/ /', $settings->get('inline_file_extensions'), -1, PREG_SPLIT_NO_EMPTY);
     }
     $extension = self::_getFileExtension($a_file_name);
     return in_array($extension, self::$_inlineFileExtensionsArray);
 }