FileUpload\FileUpload::getFileContainer PHP Method

    public function getFileContainer()
    {
        return $this->fileContainer;
    }

 /**
  * Get file_name
  * @param  string       $source_name
  * @param  string       $type
  * @param  string       $tmp_name
  * @param  integer      $index
  * @param  string       $content_range
  * @param  Pathresolver $pathresolver
  * @param  Filesystem   $filesystem
  * @return bool|string if $allowDuplicate is set to false and a file with the same Md5'd name exists in the upload directory, then a bool is returned.
  */
 public function getFileName($source_name, $type, $tmp_name, $index, $content_range, FileUpload $upload)
 {
     $filename = pathinfo($source_name, PATHINFO_FILENAME);
     $extension = pathinfo($source_name, PATHINFO_EXTENSION);
     $md5ConcatenatedName = md5($filename) . "." . $extension;
     if ($upload->getFileSystem()->doesFileExist($upload->getPathResolver()->getUploadPath($md5ConcatenatedName)) && $this->allowDuplicate === false) {
         $upload->getFileContainer()->error = "File already exist in the upload directory. Please upload another file or change it's name";
         return false;
     }
     return $md5ConcatenatedName;
 }