@startuml
participant Client order 1
participant Director order 2
participant ConcreteBuilder order 3

activate Client
  Client -> ConcreteBuilder: ConcreteBuilder()
  activate ConcreteBuilder
  Client <-- ConcreteBuilder: aConcreteBuilder
  deactivate ConcreteBuilder

  Client -> Director: Director(aConcreteBuilder)
  activate Director
  Client <-- Director: aDirector
  deactivate Director

  Client -> Director: Construct()
  activate Director
    Director -> ConcreteBuilder: BuildPartA()
    activate ConcreteBuilder
    Director <-- ConcreteBuilder
    deactivate ConcreteBuilder

    Director -> ConcreteBuilder: BuildPartB()
    activate ConcreteBuilder
    Director <-- ConcreteBuilder
    deactivate ConcreteBuilder
  Client <-- Director
  deactivate Director

  Client -> ConcreteBuilder: GetProduct()
  activate ConcreteBuilder
  Client <-- ConcreteBuilder : aProduct
  deactivate ConcreteBuilder
@enduml