/**
* @param \Jose\Object\JWEInterface $jwe
* @param \Jose\Object\JWKSetInterface $encryption_key_set
*
* @return \Jose\Object\JWSInterface
*/
private function decryptAssertion(Object\JWEInterface $jwe, Object\JWKSetInterface $encryption_key_set)
{
$this->decrypter->decryptUsingKeySet($jwe, $encryption_key_set);
$jws = $this->loader->load($jwe->getPayload());
Assertion::isInstanceOf($jws, Object\JWSInterface::class, 'The encrypted assertion does not contain a JWS.');
return $jws;
}