Pimcore\Model\Asset::setFilename PHP Method

    public function setFilename($filename)
    {
        $this->filename = (string) $filename;
        return $this;
    }

 /**
  * @param string $name
  * @return $this|void
  * @throws DAV\Exception\Forbidden
  * @throws \Exception
  */
 function setName($name)
 {
     if ($this->asset->isAllowed("rename")) {
         $user = AdminTool::getCurrentUser();
         $this->asset->setUserModification($user->getId());
         $this->asset->setFilename(\Pimcore\File::getValidFilename($name));
         $this->asset->save();
     } else {
         throw new DAV\Exception\Forbidden();
     }
     return $this;
 }