/**
  * @param Schema   $schema
  * @param Property $property
  * @param string $operationType
  * @return Operation
  */
 public static function factory(Schema $schema, Property $property, $operationType)
 {
     $operation = new self();
     $operation->setType($operationType);
     $operation->setSchema($schema);
     $operation->setPath($property->getPath());
     $operation->setValue($property->getValue());
     return $operation;
 }