/**
* Integrity check
*
* @return bool
*/
protected function integrity()
{
$result = true;
$this->progress->start(1);
$result &= array_keys($this->source->getStructure(self::SOURCE)->getFields()) == $this->structure[MapInterface::TYPE_SOURCE][self::SOURCE];
$result &= array_keys($this->destination->getStructure(self::DESTINATION)->getFields()) == $this->structure[MapInterface::TYPE_DEST][self::DESTINATION];
$this->progress->advance();
$this->progress->finish();
return (bool) $result;
}