id = $id; } /** * @return object * @throws ProtocolError */ #[\ReturnTypeWillChange] public function jsonSerialize() { if ($this->id === null) { throw new ProtocolError( 'A request without an ID is not valid' ); } $plain = parent::jsonSerialize(); $plain->id = $this->id; return $plain; } /** * @return mixed */ public function getId() { return $this->id; } /** * @param mixed $id */ public function setId($id) { $this->id = $id; } }