@startuml
Client --> ObjectStructure
ObjectStructure -> Element
Element <|-- ElementA
Element <|-- ElementB
Client --> Visitor
Visitor <|-- Visitor1
Visitor <|-- Visitor2

interface Element {
  {abstract} +Accept(Visitor*)
}
class ElementA {
  +Accept(Visitor* v) { v->VisitA(this); }
  +OperationA()
}
class ElementB {
  +Accept(Visitor* v) { v->VisitB(this); }
  +OperationB()
}

interface Visitor {
  {abstract} +VisitA(ElementA*)
  {abstract} +VisitB(ElementB*)
}
class Visitor1 {
  +VisitA(ElementA*)
  +VisitB(ElementB*)
}
class Visitor2 {
  +VisitA(ElementA*)
  +VisitB(ElementB*)
}

hide empty attributes
hide empty methods
@enduml