private function updateUsername(ChangedUsername $payload)
{
$identifier = ['userIdentifier' => $payload->userIdentifier()->toString()];
$data = [];
$data['username'] = $payload->newUsername()->toString();
$data['at'] = $payload->at()->format('Y-m-d H:i:s');
$this->connection->update($this->table, $data, $identifier);
}
/**
* @param ChangedUsername $changedUsername
*/
public function applyChangedUsername(ChangedUsername $changedUsername)
{
$this->username = $changedUsername->newUsername();
}