@startuml
skinparam BackgroundColor F0F0F0

participant "ConcreteTree" as ct
participant "ConcreteWalker" as cw
participant "ConcreteVisitor" as cv
participant "gui::Item" as item


[o->cw : traverse(root)
    create ct
        activate cw #DarkGreen
    ct <- cw : <<create>>(root)
    activate ct #DarkGreen

        create cv
        cw -> cv : <<create>>
            activate cv #DarkGreen
loop tree::hasNext()
    ct <- cw : getNext
    activate ct #LimeGreen
    ct --> cw : node
    deactivate ct
        cw -> item : accept(visitor)
                activate item #DarkGreen
            cv <- item : visit(*this)
            activate cv #LimeGreen

            cv -> item : interaction
                activate item #LimeGreen
            cv <-- item
                deactivate item

            cv --> item
            deactivate cv
        cw <-- item
                deactivate item
        cw -> cv : <<concrete interaction>>
            activate cv #LimeGreen
        cw <-- cv
            deactivate cv
end
        cw -x cv : <<delete>>
            deactivate cv
    ct x- cw : <<delete>>
    deactivate ct

@enduml