identifierRequired() public static method

public static identifierRequired ( string $documentName ) : MappingException
$documentName string
return MappingException
 /**
  * Validates the identifier mapping.
  *
  * @param ClassMetadata $class
  */
 protected function validateIdentifier($class)
 {
     if (!$class->identifier && !$class->isMappedSuperclass && !$class->isEmbeddedDocument) {
         throw MappingException::identifierRequired($class->name);
     }
 }