Jose\Object\JWSInterface::countSignatures PHP Method

    public function countSignatures();

 /**
  * {@inheritdoc}
  */
 public function sign(Object\JWSInterface &$jws)
 {
     $nb_signatures = $jws->countSignatures();
     for ($i = 0; $i < $nb_signatures; $i++) {
         $this->computeSignature($jws, $jws->getSignature($i));
     }
 }