Transcript CaseStudy_5
Optional Case Study - Chapter 5 Outline 5.1 Introduction 5.2 Collaborations 5.3 Creating Collaborations 5.4 Collaboration Diagrams 5.5 Summary 2000 Deitel & Associates, Inc. All rights reserved. 5.1 Introduction • This chapter – Last OOD assignment before we begin study of OOP in Chapter 6 – Focus on object collaboration • End of section – List of Internet and WWW UML resources (look in text) – Bibliography of UML resources (look in text) • Chapter 6 – Begin coding simulator • Chapters 7, 9 – Required to complete simulator 2000 Deitel & Associates, Inc. All rights reserved. 5.2 Collaborations • Collaboration - interaction between objects 1. Object of one class 2. Sends message 3. Received by object of another class – Message invokes operation of second class – In Chapter 4, we determined many operations • Now, we focus on the messages that invoke them • Next slide – List of verb phrases that correspond to operations • Some phrases removed from complete list of all verbs – Remaining phrases are collaborations 2000 Deitel & Associates, Inc. All rights reserved. 5.2 Collaborations (II) Cla ss Verb p hra ses Elevator resets the elevator button, sounds the elevator bell, signals its arrival to a floor, opens its door, closes its door Clock Scheduler ticks every second tells a person to step onto a floor, verifies that a floor is unoccupied Person presses floor button, presses elevator button, enters elevator, exits elevator Floor resets floor button, turns off light, turns on light FloorButton summons elevator ElevatorButton signals elevator to prepare to leave Door (opening of door) signals person to exit elevator, (opening of door) signals person to enter elevator Bell Light Building increments the time, gets the time, provides the time to the scheduler, provides the time to the elevator 2000 Deitel & Associates, Inc. All rights reserved. 5.3 Creating Collaborations • Creating Collaborations – Examine list of verbs – "resets elevator button" in class Elevator – To do this: • Elevator object sends resetButton message to ElevatorButton object • This invokes resetButton operation • Next slide – List of all collaborations that can be taken from our table of verb phrases 2000 Deitel & Associates, Inc. All rights reserved. 5.3 Creating Collaborations (II) An o b jec t o f c la ss Send s the m essa g e To a n o b jec t o f c la ss Elevator resetButton ringBell elevatorArrived openDoor closeDoor ElevatorButton Bell Floor Door Door Scheduler stepOntoFloor isOccupied Person pressButton pressButton passengerEnters passengerExits personArrives Floor resetButton turnOff turnOn Person Floor FloorButton ElevatorButton Elevator Elevator Floor FloorButton Light Light FloorButton summonElevator Elevator ElevatorButton prepareToLeave Door exitElevator enterElevator Elevator Person Person tick getTime processTime processTime Clock Clock Scheduler Elevator Clock Bell Light Building 2000 Deitel & Associates, Inc. All rights reserved. 5.4 Collaboration Diagrams • Collaboration diagrams – Model interaction of objects – Focus on which objects participate in interactions – Sequence diagrams focus on when interactions occur • Format – Rectangle - represents object, has name inside – Solid lines - connect collaborating objects • Message passed along direction shown by arrows • Name of message by arrow – Sequence of messages - numerical ordering of messages 2000 Deitel & Associates, Inc. All rights reserved. 4.2: Door sends message to waitingperson 3: Elevator 4: Elevator notifies opensfloor doorofenterElevator arrival 5.4 Collaboration Diagrams 4.1: Door 4.2.1 sends passengerEnters exitElevator message to passenger 3.1: Floor resets its button 1: Elevator resets button passengerExits 3.2:4.1.1 Floor (This turns sequence on its light ensures that a person exits before another enters) 2: Elevator rings bell : FloorButton : Light 3.1: resetButton( ) 3.2: turnOn( ) : Floor 3: elevatorArrived( ) 4.2.1: passengerEnters( ) waitingPassenger : Person 4.1.1: passengerExits( ) : Elevator passenger : Person 1: resetButton( ) 2: ringBell( ) : Bell : ElevatorButton 4: openDoor( ) 4.2: enterElevator( ) 4.1: exitElevator( ) : Door 2000 Deitel & Associates, Inc. All rights reserved. 5.5 Summary • Reasonably complete listing of classes – Chapter 6 - implement large portion of simulator – Chapter 7 - implement complete, working simulator – Chapter 9 - discuss inheritance • Summary of object-oriented design process 0. Analysis phase - meet with clients, gather information • Create use cases to describe how users interact with system • In this example, began with problem statement (no analysis phase) 1. Classes - locate classes by listing nouns in problem statement • Eliminate nouns that are attributes of classes, and nouns that are not part of the system • Create a diagram that models classes and associations 2000 Deitel & Associates, Inc. All rights reserved. 5.5 Summary • Summary of OOD process (continued) 2. Attributes - extract attributes by listing words that describe classes 3. Dynamic Nature - create statechart diagrams to learn how classes change over time 4. Operations - examine verbs associated with each class • Extract operations • Use activity diagrams to model details of operations 5. Collaborations - examine interactions between objects • Use sequence and collaboration diagrams • Add attributes and operations as needed • Design – We are probably missing a few pieces – This will become apparent as we implement the simulator in Chapter 6 2000 Deitel & Associates, Inc. All rights reserved.