@startuml
Client -> Handler
Handler <|-- ConcreteHandler

class Handler {
  -successor : Handler*
  {abstract} +Handle()
}
class ConcreteHandler {
  +Handle()
  -CanHandle() : bool
  -Do()
}

note right of Handler
  Handler::Handle() {
    successor->Handle();
  }
end note

note right of ConcreteHandler
  ConcreteHandler::Handle() {
    if (CanHandle()) { Do(); }
    else { successor->Handle(); }
  }
end note

hide empty attributes
hide empty methods
@enduml