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Does the inner style givestyle inner Doesthe behavioralcompatibility? § § the inner style inner the – { extended ; Reservation { print ; // print flight and seat // print flight inner print Date and Customer and Customer print Date print() { print() void FlightReservation seat . . .; flight . . .; // inner Reservation { Reservation } extends } date . . . ; customer . . . ; . ; customer date . . void } class } class 10/29/20 Subtyping for behaviour IN 3040 - 2020 35 , deque (ep) , often , often ended ended queue - Stack dequeue A A double ( to abbreviated deck) is an pronounced abstract data type that a queue, for generalizes elements can be which to added or removed front the either from (head) or back (tail) e; ep) { push():: insert_front pop():: delete_front dp.insert_rear Element Element s; , (ep); Dequeue dp delete_front() delete_rear() insert_front() insert_rear() Stack d; Dequeue f( Queue dp.insert_front insert_front() delete_rear() Dequeue void } ... f(s, e) = Stack Queue Dequeue Subtyping insert_rear() delete_front() delete_rear() insert_front() push() pop() delete() insert() 10/29/20 subclassing?? IN 3040 - 2020 36 A context where it isit where context A stack a as used it that sure be cannot stack. a like behaves Dequeue can take take can Dequeue a both of place the Stack a and Queue different (via references). Stack push() pop() Dequeue delete_front():: pop delete_rear() insert_front():: push insert_front():: insert_rear() Queue insert_front() delete_rear() 10/29/20 The opposite any better?anyopposite The IN 3040 - 2020 37 new extend for to new , and L with want J figures properties figures We this float a; float b; float Ellipse new Circle().color= …; …; Circle().color= new K extension float width; float float height; float ; Rectangle ? descr and and … - area color - - Figure String String FigureX float r; float Circle 10/29/20 Inheritance IN 3040 - 2020 38 : but ) variables variables of for simple simple for kind overrides description ? 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FamilyRoom ApartmentBathroom ApartmentBathroom // then use it // then with another Apartment’s rooms: // can’t be mixed class // define inner class // define the height of // reuse Kitchen Height 10/29/20 Inner classes } class IN 3040 - 2020 44 { else < Bathroom Apartment { Apartment { Apartment somewhere PinkBathroom PinkBathroom :: :: extends extends defined ApartmentBathroom syntax ahead) syntax up - PinkBathroom ApartmentBathroom ApartmentBathroom ... More fancy stuff here ...... More fancy VeryFancyApartment // SpecialApartment Apartment { Apartment } class class virtual class virtual ... } class } class }; class 10/29/20 (warning: made Virtual classes IN 3040 - 2020 45 Anonymous class ); event) { ); >() { "Hello World!" 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