@startuml
NonDerivableSingleton <-left[hidden]- BaseSingleton
BaseSingleton <|-- DerivedSingleton

class NonDerivableSingleton {
  {static} -instance : NonDerivableSingleton*
  {static} +GetInstance() : NonDerivableSingleton*
  -NonDerivableSingleton()
}
class BaseSingleton {
  {static} -instance : BaseSingleton*
  {static} -registry : Map<String, BaseSingleton*>
  __
  {static} +GetInstance() : BaseSingleton*
  #BaseSingleton()
  ..
  {static} #Register(String, BaseSingleton*)
  {static} #LookUp(String) : BaseSingleton*
}
class DerivedSingleton {
  {static} -instance : DerivedSingleton*
  {static} +GetInstance() : DerivedSingleton*
  #DerivedSingleton()
}

note left of DerivedSingleton
  DerivedSingleton::DerivedSingleton() {
    BaseSingleton::Register("DerivedSingleton", this);
  }
end note
@enduml