car_visitor.puml

@startuml
skinparam classAttributeIconSize 0

' Ensure vertical layout
left to right direction

interface "Interface \n CarElement" as CarElement
{
+{abstract} accept(CarElementVisitor *visitor):void
}

interface "Interface \n CarElementVisitor" as CarElementVisitor
{
    +{abstract} visit(Body *body):void
    +{abstract} visit(Car *car):void
    +{abstract} visit(Engine *engine):void
    +{abstract} visit(Wheel *wheel):void
}

CarElement <|-- Body
CarElement <|-- Wheel
CarElement <|-- Engine
CarElement <|-- Car

CarElementVisitor <|-- CarElementDoVisitor
CarElementVisitor <|-- CarElementPrintVisitor

class Wheel
{
private:
    string name;
public:
    + Wheel(string name):void
    + getName():string
    + accept(CarElementVisitor *visitor):void
}

note " visitor->visit(this)" as Wheelaccept

class Body 
{
   + accept(CarElementVisitor *visitor)
}

class Engine 
{
    accept(CarElementVisitor *visitor):void
}

class Car
{
-   vector<CarElement*> elements;
+   Car()
+    accept(CarElementVisitor *visitor):void
}

note "this->elements = std::vector<CarElement*>{\n new Wheel('front left'), new Wheel('front right'),\n new Wheel('back left'), new Wheel('back right'),\n new Body(), new Engine()}" as CarConstruct

note "for (CarElement* element : elements)\n {element->accept(visitor);\n  }\n         visitor->visit(this);" as CarAccept

class CarElementDoVisitor 
{
    + visit(Body *body):void
    + visit(Car *car):void
    + visit(Wheel *wheel):void
    + visit(Engine *engine):void
}

class CarElementPrintVisitor
{
    +visit(Body *body):void 
    + visit(Car *car):void 
    + visit(Engine *engine):void 
    + visit(Wheel *wheel):void 
}

Wheelaccept -up..Wheel::accept

CarConstruct -down..Car::Car
CarAccept -up..Car::accept
@enduml