1. To navigate the slide presentation, use the navigation bar on the left OR use your right and left arrow keys. Move your mouse over the key terms throughout the presentation to see a definition. Click to view reference figures. For further exploration, links to selected Web sites are included. Click under this banner throughout the presentation. Chapter 5 Home Page – Welcome!

2. 2 Chapter Objectives  Explain how object-oriented analysis can be used to describe an information system  Define object modeling terms and concepts, including objects, attributes, methods, messages, classes, and instances  Explain relationships among objects and the concept of inheritance  Draw an object relationship diagram

3. 3 Chapter Objectives  Describe Unified Modeling Language (UML) tools and techniques, including use cases, use case diagrams, class diagrams, sequence diagrams, state transition diagrams, and activity diagrams  Explain the advantages of using CASE tools in developing the object model  Explain how to organize an object model

4. 4 Introduction  You will learn about object-oriented analysis, which is another way to view and model system requirements  You will learn how to use object-oriented methods to document, analyze, and model an information system

5. 5 Object-Oriented Terms and Concepts  Object-oriented (O-O) analysis Object-oriented (O-O) analysis  Object Object  Object-oriented analysis is a popular approach that sees a system from the viewpoint of the objects themselves as they function and interact  Object model Object model For more information about Object-Oriented Analysis, visit scsite.com/sad7e/more,scsite.com/sad7e/more locate Chapter 5 and then the Object-Oriented Analysis link.

6. 6 Object-Oriented Terms and Concepts  Overview of O-O Analysis –Unified Modeling Language (UML)Unified Modeling Language (UML) –AttributesAttributes –MethodsMethods –MessageMessage –ClassClass –InstanceInstance Figure 5-3 For more information about Unified Modeling Language, visit scsite.com/sad7e/more,scsite.com/sad7e/more locate Chapter 5 and then the Unified Modeling Language link. Figure 5-2

7. 7 Object-Oriented Terms and Concepts  Objects –Consider how the UML describes a family with parents and children –The UML represents an object as a rectangle with the object name at top, followed by the object’s attributes and methods Figure 5-4 Figure 5-5

8. 8 Object-Oriented Terms and Concepts  Objects –The CHILD object possesses the same attributes as the PARENT object and an additional attribute that shows the number of siblings –A CHILD object performs certain methods –The family might also have a DOG object Figure 5-6

9. 9 Object-Oriented Terms and Concepts  Objects –Now consider an example of a fitness center, and the objects that interact with the fitness center’s enrollment system –A typical fitness center might have students, instructors, fitness-class schedules, and a registration process Figure 5-8 Figure 5-9 Figure 5-10

10. 10 Object-Oriented Terms and Concepts  Attributes –If objects are similar to nouns, attributes are similar to adjectives that describe the characteristics of an object –Some objects might have a few attributes; others might have dozens –StateState

11. 11 Object-Oriented Terms and Concepts  Methods –A method defines specific tasks that an object can perform –Just as objects are similar to nouns and attributes are similar to adjectives, methods resemble verbs that describe what and how an object does something Figure 5-11 Figure 5-12 Figure 5-13

12. 12 Object-Oriented Terms and Concepts  Messages –PolymorphismPolymorphism –Black boxBlack box –EncapsulationEncapsulation –Object-oriented designs typically are implemented with object-oriented programming languages Figure 5-14 Figure 5-15 For more information about Polymorphism, visit scsite.com/sad7e/more, scsite.com/sad7e/more locate Chapter 5 and then the Polymorphism link.

13. 13 Object-Oriented Terms and Concepts  Messages –A major advantage of O-O designs is that systems analysts can save time and avoid errors by using modular objects, and programmers can translate the designs into code, working with reusable program modules that have been tested and verified Figure 5-16

14. 14 Object-Oriented Terms and Concepts  Classes –An object belongs to a group or category called a class –All objects within a class share common attributes and methods –SubclassesSubclasses –SuperclassSuperclass Figure 5-17 Figure 5-18 Figure 5-19

15. 15 Relationships Among Objects and Classes  Relationships Relationships  Relationships describe what objects need to know about each other  Inheritance Inheritance  Child Child  Parent Parent Figure 5-20

16. 16 Relationships Among Objects and Classes  Object Relationship Diagram –After you identify the objects, classes, and relationships, you are ready to prepare an object relationship diagram that will provide an overview of the system –You will use that model as a guide as you continue to develop additional diagrams and documentation Figure 5-21

17. 17 Object Modeling with the Unified Modeling Language  The UML uses a set of symbols to represent graphically the various components and relationships within a system  It mainly is used to support object- oriented system analysis and to develop object models For more information about Use Case Modeling, visit scsite.com/sad7e/more, scsite.com/sad7e/more locate Chapter 5 and then the Use Case Modeling link.

18. 18 Object Modeling with the Unified Modeling Language  Use Case Modeling Use Case –ActorActor –Symbol for a use case is an oval with a label that describes the action or event –Use cases also can interact with other use cases Figure 5-23 Figure 5-22

19. 19 Object Modeling with the Unified Modeling Language  Use Case Modeling –When the outcome of one use case is incorporated by another use case, we say that the second case uses the first case –Use case descriptionUse case description –When you identify use cases, try to group all the related transactions into a single use case Figure 5-24 Figure 5-25

20. 20 Object Modeling with the Unified Modeling Language  Use Case Diagrams –Use case diagramUse case diagram –System boundarySystem boundary –After you identify the system boundary, you place the use cases on the diagram, add the actors, and show the relationships Figure 5-26 Figure 5-27 For more information about Use Case Diagrams, visit scsite.com/sad7e/more, scsite.com/sad7e/more locate Chapter 5 and then the Use Case Diagrams link. Figure 5-28

21. 21 Object Modeling with the Unified Modeling Language  Class Diagrams Class Diagrams –Evolves into a physical model and finally becomes a functioning information system –Each class appears as a rectangle, with the class name at the top, followed by the class’s attributes and methods –CardinalityCardinality Figure 5-29 Figure 5-30

22. 22 Object Modeling with the Unified Modeling Language  Sequence Diagrams –Sequence diagramSequence diagram –Include Classes Lifelines Messages Focuses Figure 5-31 Figure 5-32

23. 23 Object Modeling with the Unified Modeling Language  State Transition Diagrams State Transition –A state transition diagram shows how an object changes from one state to another, depending on events that affect the object –In a state transition diagram, the states appear as rounded rectangles with the state names inside Figure 5-33

24. 24 Object Modeling with the Unified Modeling Language  State Transition Diagrams –The small circle to the left is the initial state, or the point where the object first interacts with the system –Reading from left to right, the lines show direction and describe the action or event that causes a transition from one state to another –The circle at the right with a hollow border is the final state

25. 25 Object Modeling with the Unified Modeling Language  Activity Diagrams –Activity diagramActivity diagram –Show the order in which the actions take place and identify the outcomes –Also can display multiple use cases in the form of a grid, where classes are shown as vertical bars and actions appear as horizontal arrows Figure 5-34

26. 26 Object Modeling with the Unified Modeling Language  Activity Diagrams –Sequence diagrams, state transition diagrams, and activity diagrams are dynamic modeling tools that can help a systems analyst understand how objects behave and interact with the system

27. 27 Object Modeling with the Unified Modeling Language  CASE Tools –Object modeling requires many types of diagrams to represent the proposed system –Creating the diagrams by hand is time- consuming and tedious, so systems analysts rely on CASE tools to speed up the process and provide an overall framework for documenting the system components

28. 28 Organizing the Object Model  Organizing the Object Model –You should organize your use cases and use case diagrams so they can be linked to the appropriate class, state transition, sequence, and activity diagrams –It is much easier to repair a diagram now than to change the software later

29. 29 Chapter Summary  This toolkit introduces object modeling, which is a popular technique that describes a system in terms of objects  The Unified Modeling Language (UML) is a widely used method of visualizing and documenting an information system  At the end of the object modeling process, you organize your use cases and use case diagrams and create class, sequence, state transition, and activity diagrams

30. 30 Test Yourself  True/False: Object models are part of structured analysis and design.

31. 31 Test Yourself  True/False: Object models are part of structured analysis and design. False

32. 32 Test Yourself  A ________ defines specific tasks that an object can perform.

33. 33 Test Yourself  A method defines specific tasks that an object can perform.

34. 34  Drive car is an example of a/an ______ while engine is an example of a/an ______. Test Yourself

35. 35 Test Yourself  Drive car is an example of an attribute while engine is an example of a message.

36. 36 Test Yourself  True/False: In UML, an object’s methods are listed after it’s attributes.

37. 37 Test Yourself  True/False: In UML, an object’s methods are listed after it’s attributes. True

38. 38 Test Yourself 5.List at least two possible subclasses for a cat class.

39. 39 Test Yourself 5.List at least two possible subclasses for a cat class. House Cat Outdoor Cat

40. 40 Test Yourself  What are the symbols for an actor and for a use case?

41. 41 Test Yourself  What are the symbols for an actor and for a use case? Actor Use Case

42. 42 Test Yourself  __________ are part of a sequence diagram.  Lifeline  Focus  Class  None of the above  All of the above

43. 43 Test Yourself  __________ are part of a sequence diagram.  Lifeline  Focus  Class  None of the above  All of the above

44. 44 Test Yourself  0..* signifies a ____ relation while 1..* signifies a _____ relation.

45. 45 Test Yourself  0..* signifies a zero or many relation while 1..* signifies a one or many relation.

46. 46 Test Yourself  True/False: It is easy to modify an object model after software has been constructed.

47. 47 Test Yourself  True/False: It is easy to modify an object model after software has been constructed. False

48. 48 Test Yourself  A/an _________ diagram resembles a horizontal flowchart.

49. 49 Test Yourself  An activity diagram resembles a horizontal flowchart.

50. Systems Analysis & Design 7 th Edition End Chapter 5