class UiLinkId {

    private UiLinkId(ElementId a, PortNumber pa, ElementId b, PortNumber pb) {
        idA = a;
        portA = pa;
        idB = b;
        portB = pb;

        idStr = a + ID_PORT_DELIMITER + pa + CP_DELIMITER +
                b + ID_PORT_DELIMITER + pb;
    }

    private  UiLinkId(ElementId a, PortNumber pa, ElementId b, PortNumber pb);

}