/** * @param string $key * @return null */ public function setKey($key) { if (!isset($this->loadedFields['key'])) { $this->loadProperties(); } $oldValue = null; if (array_key_exists('key', $this->loadedValues)) { $oldValue = $this->loadedValues['key']; } if ($oldValue === $key) { $this->key = $key; return; } return parent::setKey($key); }