/**
  * {@inheritdoc}
  * @throws Exception\StandardException
  */
 public function setValue($value)
 {
     if ($this->hasReference()) {
         throw new Exception\StandardException('Readonly Item', $this->getId(), "It can't be overwritten, because it has references to the other.");
     } else {
         parent::setValue($value);
     }
     return $this;
 }