2. Using UML, Patterns, and Java Object-Oriented Software Engineering Chapter 2, Modeling with UML

3. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 2 Overview: modeling with UML  What is modeling?  What is UML?  Use case diagrams  Class diagrams  Sequence diagrams  Activity diagrams

4. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 3 What is modeling?  Modeling consists of building an abstraction of reality.  Abstractions are simplifications because:  They ignore irrelevant details and  They only represent the relevant details.  What is relevant or irrelevant depends on the purpose of the model.

5. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 4 Example: street map

6. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 5 Why model software?  Software is getting increasingly more complex  Windows XP > 40 millions of lines of code  A single programmer cannot manage this amount of code in its entirety.  Code is not easily understandable by developers who did not write it  We need simpler representations for complex systems  Modeling is a mean for dealing with complexity

7. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 6 Systems, Models and Views  A model is an abstraction describing a subset of a system  A view depicts selected aspects of a model  A notation is a set of graphical or textual rules for depicting views  Views and models of a single system may overlap each other Examples:  System: Aircraft  Models: Flight simulator, scale model  Views: All blueprints, electrical wiring, fuel system

8. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 7 Systems, Models and Views Aircraft Flightsimulator Scale Model Blueprints Electrical Wiring

9. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 8 Models, Views and Systems (UML) SystemModelView * * Depicted by Described by Airplane: System Blueprints: ViewFuel System: ViewElectrical Wiring: View Scale Model: Model Flight Simulator: Model

10. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 9 Concepts and Phenomena Phenomenon  An object in the world of a domain as you perceive it  Example: The lecture you are attending  Example: My black watch Concept  Describes the properties of phenomena that are common.  Example: Lectures on software engineering  Example: Black watches Concept is a 3-tuple:  Name (To distinguish it from other concepts)  Purpose (Properties that determine if a phenomenon is a member of a concept)  Members (The set of phenomena which are part of the concept)

11. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 10  Abstraction  Classification of phenomena into concepts  Modeling  Development of abstractions to answer specific questions about a set of phenomena while ignoring irrelevant details. MembersName Clock Purpose A device that measures time. Concepts and phenomena

12. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 11 Concepts in software: Type and Instance  Type:  An abstraction in the context of programming languages  Name: int, Purpose: integral number, Members: 0, -1, 1, 2, -2,...  Instance:  Member of a specific type  The type of a variable represents all possible instances the variable can take The following relationships are similar:  “type” “instance”  “concept” “phenomenon”

13. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 12 Abstract Data Types & Classes  Abstract data type  Special type whose implementation is hidden from the rest of the system.  Class:  An abstraction in the context of object- oriented languages  Like an abstract data type, a class encapsulates both state (variables) and behavior (methods)  Class Vector  Unlike abstract data types, classes can be defined in terms of other classes using inheritance

14. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 13 Application and Solution Domain  Application Domain (Requirements Analysis):  The environment in which the system is operating  Solution Domain (System Design, Object Design):  The available technologies to build the system

15. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 14 Object-oriented modeling Application DomainSolution Domain Application Domain ModelSystem Model Aircraft TrafficController FlightPlan Airport MapDisplay FlightPlanDatabase SummaryDisplay TrafficControl UML Package

16. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 15 What is UML?  UML (Unified Modeling Language)  An emerging standard for modeling object-oriented software.  Resulted from the convergence of notations from three leading object-oriented methods:  OMT (James Rumbaugh)  OOSE (Ivar Jacobson)  Booch (Grady Booch)  Reference: “The Unified Modeling Language User Guide”, Addison Wesley, 1999.  Supported by several CASE tools  Rational ROSE  Eclipse/UML (by Omondo)  Gentleware Poseidon  TogetherJ

17. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 16 UML  You can model 80% of most problems by using about 20 % UML  We teach you those 20%

18. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 17 UML First Pass  Use case Diagrams  Describe the functional behavior of the system as seen by the user.  Class diagrams  Describe the static structure of the system: Objects, Attributes, Associations  Sequence diagrams  Describe the dynamic behavior between actors and the system and between objects of the system  Statechart diagrams  Describe the dynamic behavior of an individual object (essentially a finite state automaton)  Activity Diagrams  Model the dynamic behavior of a system, in particular the workflow (essentially a flowchart)

19. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 18 UML Core Conventions  Rectangles are classes, instances (objects) or states  Ovals are functions or use cases  Instances are denoted with an underlined names  myWatch:SimpleWatch  Joe:Firefighter  Types are denoted with non underlined names  SimpleWatch  Firefighter  Diagrams are graphs  Nodes are entities  Arcs are relationships between entities

20. Using UML, Patterns, and Java Object-Oriented Software Engineering UML second pass Use Case diagrams

21. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 20 UML first pass: Use case diagrams WatchUserWatchRepairPerson ReadTimeSetTime ChangeBattery Actor Use case Package Watch Use case diagrams represent the functionality of the system from user’s point of view (behavior)

22. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 21 Use Case Diagrams  Used during requirements elicitation to represent external behavior  Actors represent roles, that is, a type of user of the system  Use cases represent a sequence of interaction for a type of functionality  The use case model is the set of all use cases. It is a complete description of the functionality of the system and its environment Passenger PurchaseTicket

23. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 22 Actors  An actor models an external entity which communicates with the system:  User  External system  Physical environment  An actor has a unique name and an optional description.  Examples:  Passenger: A person in the train  GPS satellite: Provides the system with GPS coordinates Passenger

24. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 23 Use Case A use case represents a class of functionality provided by the system as an event flow. A use case consists of:  Unique name  Participating actors  Entry conditions  Flow of events  Exit conditions  Special requirements PurchaseTicket

25. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 24 Use Case Diagram: Example Name: Purchase ticket Participating actor: Passenger Entry condition:  Passenger standing in front of ticket distributor.  Passenger has sufficient money to purchase ticket. Exit condition:  Passenger has ticket. Event flow: 1. Passenger selects the number of zones to be traveled. 2. Distributor displays the amount due. 3. Passenger inserts money, of at least the amount due. 4. Distributor returns change. 5. Distributor issues ticket. Anything missing ? Exceptional cases!

26. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 25 The > Relationship  > relationships represent exceptional or seldom invoked cases.  The exceptional event flows are factored out of the main event flow for clarity.  Use cases representing exceptional flows can extend more than one use case.  The direction of a > relationship is to the extended use case Passenger PurchaseTicket TimeOut > NoChange > OutOfOrder > Cancel >

27. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 26 The > Relationship  > relationship represents behavior that is factored out of the use case.  > behavior is factored out for reuse, not because it is an exception.  The direction of a > relationship is to the using use case (unlike > relationships). Passenger PurchaseSingleTicketPurchaseMultiCard NoChange > Cancel > CollectMoney >

28. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 27 Other examples OpenIncident AllocateResources HelpDispatcher > OpenIncident Allocate Resources Connection Down > Authenticate WithPassword WithCard

29. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 28 Use Case Diagrams: Summary  Use case diagrams represent external behavior  Use case diagrams are useful as an index into the use cases  Use case descriptions provide meat of model, not the use case diagrams.  All use cases need to be described for the model to be useful.

30. Using UML, Patterns, and Java Object-Oriented Software Engineering UML second pass Class diagrams

31. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 30 UML first pass: Class diagrams 1 2 push() release() 1 1 blinkIdx blinkSeconds() blinkMinutes() blinkHours() stopBlinking() referesh() LCDDisplayBattery load 1 2 1 Time now 1 Watch Class Association Multiplicity Attribute Operations Class diagrams represent the structure of the system state PushButton

32. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 31 Class Diagrams  Class diagrams represent the structure of the system.  Used  during requirements analysis to model problem domain concepts  during system design to model subsystems and interfaces  during object design to model classes. Enumeration getZones() Price getPrice(Zone) TarifSchedule * * Trip zone:Zone Price: Price

33. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 32 Classes  A class represent a concept  A class encapsulates state (attributes) and behavior (operations).  Each attribute has a type.  Each operation has a signature.  The class name is the only mandatory information. zone2price getZones() getPrice() TarifSchedule Table zone2price Enumeration getZones() Price getPrice(Zone) TarifSchedule Name Attributes Operations Signature TarifSchedule

34. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 33 Attributes and operations visibility Attributes visibility  They should always be private (  information hiding)  Other classes can access an attribute value using get and set methods Operation visibility  + : public (the operation is part of the class interface)  - : private (the operation can only be accessed by the class itself)  #: protected (in abstract classes, operations that can be used by subclasses only).  This visibility constraint, in abstract classes, can also be used for attributes

35. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 34 Instances  An instance represents a phenomenon.  The name of an instance is underlined and can contain the class of the instance.  The attributes are represented with their values. zone2price = { {‘1’,.20}, {‘2’,.40}, {‘3’,.60}} tarif_1974:TarifSchedule

36. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 35 Actor vs Instances  What is the difference between an actor, a class and an instance?  Actor:  A coherent set of roles that users of use cases play when interacting with these use cases. An actor has one role for each use case with which it communicates. (UML 1.5 definition)  An entity outside the system to be modeled, interacting with the system (“Passenger”) (book definition)  Class:  An abstraction modeling an entity in the problem domain, must be modeled inside the system (“User”)  Object:  A specific instance of a class (“Joe, the passenger who is purchasing a ticket from the ticket distributor”).

37. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 36 Price Zone Associations  Associations denote relationships between classes.  The multiplicity of an association end denotes how many objects the source object can legitimately reference. Enumeration getZones() Price getPrice(Zone) TarifScheduleTripLeg * *

38. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 37 1-to-1 and 1-to-many Associations Country name:String City name:String Has-capital Polygon draw() Point x: Integer y: Integer One-to-one association One-to-many association * *

39. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 38 Many-to-Many Associations StockExchange Company tickerSymbol Lists **

40. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 39 From Problem Statement To Object Model Problem Statement: A stock exchange lists many companies. Each company is uniquely identified by a ticker symbol Class Diagram: StockExchange Company tickerSymbol Lists **

41. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 40 From Problem Statement to Code public class StockExchange { private Vector m_Company = new Vector(); }; public class Company { public int m_tickerSymbol; private Vector m_StockExchange = new Vector(); }; Problem Statement:A stock exchange lists many companies. Each company is identified by a ticker Symbol Class Diagram: Java Code StockExchange Company tickerSymbol Lists * *

42. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 41 Aggregation  An aggregation is a special case of association denoting a “consists of” hierarchy.  The aggregate is the parent class, the components are the children class.  A solid diamond denotes composition, a strong form of aggregation where components cannot exist without the aggregate. (Bill of Material) TicketMachineZoneButton 3 Exhaust system Muffler diameter Tailpipe diameter 1 0..2 Exhaust system Muffler diameter Tailpipe diameter 1 0..2

43. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 42 Qualifiers  Qualifiers can be used to reduce the multiplicity of an association. Directory File filename Without qualification 1* With qualification DirectoryFile 0…1 1 filename

44. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 43 Inheritance (Generalization)  Generalization relationships denote inheritance between classes.  The children classes inherit the attributes and operations of the parent class.  Inheritance simplifies the model by eliminating redundancy. Button ZoneButtonCancelButton

45. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 44 Object Modeling in Practice: Class Identification Foo Betrag CustomerId Deposit() Withdraw() GetBalance() Class Identification: Name of Class, Attributes and Methods

46. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 45 Object Modeling in Practice: Encourage Brainstorming Foo Betrag CustomerId Deposit() Withdraw() GetBalance() Account Betrag CustomerId Deposit() Withdraw() GetBalance() Naming is important! Is Foo the right name? “Dada” Betrag CustomerId Deposit() Withdraw() GetBalance()

47. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 46 Object Modeling in Practice ctd Account Betrag Deposit() Withdraw() GetBalance() Customer Name CustomerId 1) Find New Objects CustomerId AccountId 2) Iterate on Names, Attributes and Methods Bank Name

48. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 47 Object Modeling in Practice: A Banking System Account Betrag Deposit() Withdraw() GetBalance() Customer Name CustomerId AccountI d Bank Name 1) Find New Objects 2) Iterate on Names, Attributes and Methods 3) Find Associations between Objects Has 4) Label the assocations 5) Determine the multiplicity of the assocations *

49. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 48 Practice Object Modeling: Iterate, Categorize! Customer Name CustomerId() Account Amount Deposit() Withdraw() GetBalance() CustomerId AccountI d Bank Name Has * * Savings Account Withdraw() Checking Account Withdraw() Mortgage Account Withdraw()

50. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 49 Packages  A package is a UML mechanism for organizing elements into groups (usually not an application domain concept)  Packages are the basic grouping construct with which you may organize UML models to increase their readability.  A complex system can be decomposed into subsystems, where each subsystem is modeled as a package DispatcherInterface Notification IncidentManagement

51. Using UML, Patterns, and Java Object-Oriented Software Engineering UML second pass Sequence diagrams

52. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 51 UML first pass: Sequence diagram :LCDDisplay blinkHours() blinkMinutes() refresh() commitNewTime() :Time incrementMinutes() stopBlinking() :Watch pressButton1() pressButton2() pressButtons1And2() pressButton1() :WatchUser Object Message Activation Sequence diagrams represent the behavior as interactions Actor Lifeline

53. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 52 UML sequence diagrams  Used during requirements analysis  To refine use case descriptions  to find additional objects (“participating objects”)  Used during system design  to refine subsystem interfaces  Classes are represented by columns  Messages are represented by arrows  Activations are represented by narrow rectangles  Lifelines are represented by dashed lines selectZone() pickupChange() pickUpTicket() insertCoins() Passenger TicketMachine

54. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 53 Nested messages  The source of an arrow indicates the activation which sent the message  An activation is as long as all nested activations  Horizontal dashed arrows indicate data flow  Vertical dashed lines indicate lifelines selectZone() Passenger ZoneButton TarifScheduleDisplay lookupPrice(selection) displayPrice(price) price Dataflow …to be continued...

55. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 54 Iteration & condition  Iteration is denoted by a * preceding the message name  Condition is denoted by boolean expression in [ ] before the message name Passenger ChangeProcessor insertChange(coin) CoinIdentifierDisplayCoinDrop displayPrice(owedAmount) lookupCoin(coin) price [owedAmount<0] returnChange(-owedAmount) Iteration Condition …to be continued... …continued from previous slide... *

56. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 55 Creation and destruction  Creation is denoted by a message arrow pointing to the object.  Destruction is denoted by an X mark at the end of the destruction activation.  In garbage collection environments, destruction can be used to denote the end of the useful life of an object. Passenger ChangeProcessor …continued from previous slide... Ticket createTicket(selection) free() Creation Destruction print()

57. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 56 Condizioni e iterazioni abc [i>0] op1() [i<=0] op2() *op3()

58. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 57 Sequence Diagram Summary  UML sequence diagram represent behavior in terms of interactions.  Useful to find missing objects.  Time consuming to build but worth the investment.  Complement the class diagrams (which represent structure).

59. Using UML, Patterns, and Java Object-Oriented Software Engineering UML second pass State diagrams

60. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 59 UML First Pass: Statechart Diagrams Statechart diagram for class Incident State Initial state Final state Transition Event

61. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 60 UML First Pass: Statechart Diagrams Statechart of the 2BWatch set time functions

62. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 61 State Diagrams  A state is a condition that an object satisfies  A state can be thought of as an abstraction of the attribute values of a class  A state diagram can be used to describe:  The life of a class  The life of a system/subsystem referred to as a whole  The navigational paths among the different windows of an application GUI

63. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 62 State Diagram (from UML 1.5 pag. 537)

64. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 63 State internal actions/activities (from UML 1.5 pag. 538) Reserved action labels: Internal actions syntax: event-name ‘(’ comma-separated-parameter-list ‘)’ ‘[’ guard-condition‘]’ ‘/’action-expression Example: click on button X [var_y=1]/ do_something

65. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 64 Composite state Guard Condition

66. Using UML, Patterns, and Java Object-Oriented Software Engineering UML second pass Activity diagrams

67. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 66 Activity Diagram: Modeling Decisions

68. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 67 Activity diagrams: concurrency

69. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 68 Activity Diagrams  An activity diagram shows flow control within a system  An activity diagram is a special case of a state chart diagram in which states are activities (“functions”)  Two types of states:  Action state:  Cannot be decomposed any further  Happens “instantaneously” with respect to the level of abstraction used in the model  Activity state:  Can be decomposed further  The activity is modeled by another activity diagram

70. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 69 Activity diagrams key concepts  In an activity diagram:  states represent the performance of actions or subactivities  transitions are triggered by the completion of the actions or subactivities.  A subactivity state invokes an activity graph. When a subactivity state is entered, the activity graph “nested” in it is executed as any activity graph would be.  Action definition (from UML 1.5):  The specification of an executable statement that is part of a computational procedure.  An action typically results in a change in the state of the system, and can be realized by sending a message to an object or modifying a link or a value of an attribute.

71. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 70 Statechart Diagram vs. Activity Diagram ActiveInactive Closed Archived Incident- Handled Incident- Documented Incident- Archived Statechart Diagram for Incident (State: Attribute or Collection of Attributes of object of type Incident) Activity Diagram for Incident (similar to Moore (State: Operation or Collection of Operations) Triggerless Transition Completion of activity causes state transition Event causes State transition

72. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 71 Activity Diagram: Modeling Decisions

73. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 72 Activity Diagrams: Modeling Concurrency  Synchronization of multiple activities  Splitting the flow of control into multiple threads Synchronization Splitting

74. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 73 Activity Diagrams: Swimlanes  Actions may be grouped into swimlanes to denote the object or subsystem that implements the actions. Open Incident Allocate Resources Coordinate Resources Document Incident Archive Incident Dispatcher FieldOfficer

75. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 74 Activity diagram (from UML 1.5 pag.557)

76. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 75 Activity diagram (from UML 1.5 pag.562)

77. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 76 Activity diagram (from UML 1.5 pag.562) Data flows (objects)

78. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 77 What should be done first? Coding or Modeling?  It all depends….  Forward Engineering:  Creation of code from a model  Greenfield projects  Reverse Engineering:  Creation of a model from code  Interface or reengineering projects  Roundtrip Engineering:  Move constantly between forward and reverse engineering  Useful when requirements, technology and schedule are changing frequently

79. Using UML, Patterns, and Java Object-Oriented Software Engineering UML second pass Component and Deployment diagrams

80. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 79 Other UML Notations UML provide other notations that we will be introduced in subsequent lectures, as needed.  Implementation diagrams  Component diagrams  Deployment diagrams  Object Constraint Language (OCL)  Introduced in lecture on Object Design

81. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 80 Component diagrams key concepts  A component represents a modular, deployable, and replaceable part of a system that encapsulates implementation and exposes a set of interfaces.  A component conforms to the interfaces that it exposes, where the interfaces represent services provided by elements that reside on the component.  A component may be implemented by one or more artifacts, such as binary, executable, or script files.  A component may be deployed on a node.

82. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 81 Component diagrams Component Interface Components typically expose a set of interfaces, which represent the services provided by the elements that reside on the component.

83. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 82 Component and Deployment diagrams key concepts  A node is a physical object that represents a processing resource, generally, having at least a memory and often processing capability as well.  Nodes include computing devices but also human resources or mechanical processing resources.  Run time computational instances, both objects and component instances, may reside on node instances.

84. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 83 Deployment Diagrams

85. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 84 UML Core Conventions  Rectangles are classes or instances  Ovals are functions or use cases  Instances are denoted with an underlined names  myWatch:SimpleWatch  Joe:Firefighter  Types are denoted with nonunderlined names  SimpleWatch  Firefighter  Diagrams are graphs  Nodes are entities  Arcs are relationships between entities

86. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 85 UML Summary  UML provides a wide variety of notations for representing many aspects of software development  Powerful, but complex language  Can be misused to generate unreadable models  Can be misunderstood when using too many exotic features  For now we concentrate on a few notations:  Functional model: Use case diagram  Object model: class diagram  Dynamic model: sequence diagrams, statechart and activity diagrams

87. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 86 Additional Slides

88. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 87 Models for Plato’s and Aristotle’s Views of Reality Plato  Material reality is a second-class subordinate type of reality.  The first-class type is a “form” Forms lie behind every thing or in the world. Forms can be abstract nouns like “beauty” or “mammal” or concrete nouns like “tree” or “horse”.  There is an important difference between the world of forms and particulars. Forms are nonmaterial, particulars are material. Forms are permanent and changeless. Particulars are changing.  Forms can be acquired intellectually through a “dialectic” process that moves toward the highest understanding of reality through the interaction of questions and answers.  Aristotle accepted the reality of Forms as nonmaterial entities.  However, he could not accept Plato’s idea, that these Forms were not real.  Instead of two separate worlds, one for Forms and one for Particulars, Aristotle had only one world, a world of particular things.  Particular things according to Aristotle have a certain permance about them, even while they are subject to change: A tree changes colors without ceasing to be a tree. A horse grows in size without ceasing to be a horse.  What is the root of this permancence? It is the thing’s internal form, which minds detect, when they penetrate beyond the thing’s changing attributes. So for Aristotle, reality is thus made up of particular things that are each composed of form antdn matter.. Aristotle Using UML, we can illustrate Platon’s and Aristotle’s viewpoints very easily and see their differences as well

89. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 88 Model for Plato’s View of Reality Plato  Material reality is a second- class subordinate type of reality.  The first-class type is a “form” Forms lie behind every thing or in the world. Forms can be abstract nouns like “beauty” or “mammal” or concrete nouns like “tree” or “horse”.  There is an important difference between the world of forms and particulars. Forms are nonmaterial, particulars are material. Forms are permanent and changeless. Particulars are changing.  Forms can be acquired intellectually through a “dialectic” process that moves toward the highest understanding of reality through the interaction of questions and answers.

90. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 89 Model Aristotle’s Views of Reality Aristotle  Aristotle accepted the reality of Forms as nonmaterial entities.  However, he could not accept Plato’s idea, that these Forms were not real.  Instead of two separate worlds, one for Forms and one for Particulars, Aristotle had only one world, a world of particular things.  Particular things according to Aristotle have a certain permance about them, even while they are subject to change: A tree changes colors without ceasing to be a tree. A horse grows in size without ceasing to be a horse.  What is the root of this permancence? It is the thing’s internal form, which minds detect, when they penetrate beyond the thing’s changing attributes. So for Aristotle, reality is thus made up of particular things that are each composed of form antdn matter..

91. Bernd Bruegge & Allen H. Dutoit Object-Oriented Software Engineering: Using UML, Patterns, and Java 90 Comparison of Plato’s and Aristotle’s Views Plato Aristotle