/**
* {@inheritdoc}
*/
public function acquireToken($duration = NULL, $force = FALSE)
{
$token = $this->tokenCache->get();
if ($force || !$token || $this->tokenCache->isMiss() || $this->tokenCache->getExpiration()->getTimestamp() <= time() + $duration) {
if ($token) {
$this->signOut();
}
$token = $this->signIn();
}
return $token;
}