1Software EngineeringRecitation 3Suhit GuptaReviewn CVS problemsn XML problems –XML/XSD/DTD/SCHEMASToday we will be covering…n UML, UML and more UML…n Some Visio and some Rose.2Agendan Benefits of Visual Modelingn History of the UMLn Visual Modeling with UMLn The Rational Iterative Development ProcessWhat is Visual Modeling?Business ProcessOrderItemShip viaVisual Modeling is modelingusing standard graphical notationsComputer System“Modeling captures essential parts of the system.”Dr. James RumbaughVisual Modeling Captures Business ProcessUse Case Analysis is a technique to capture business process from user’s perspective3Visual Modeling - Communication ToolUse visual modeling to capture business objects and logicUse visual modeling to analyze and design your applicationVisual Modeling Manages ComplexityDatabase Server(C++ & SQL)Model your systemindependent of implementation languageVisual Modeling Defines Software ArchitectureUser Interface(Visual Basic,Java)Business Logic(C++, Java)4Multiple SystemsVisual Modeling Promotes ReuseReusableComponentsWhat is the UML?n UML stands for Unified Modeling Languagen The UML combines the best of the best from– Data Modeling concepts (Entity Relationship Diagrams)– Business Modeling (work flow)– Object Modeling – Component Modelingn The UML is the standard language for visualizing, specifying, constructing, and documenting the artifacts of a software-intensive systemn It can be used with all processes, throughout the development life cycle, and across different implementation technologiesHistory of the UMLNov ‘97 UML approved by the OMG5Class Diagramsn A class diagram shows the existence of classes and their relationships in the logical view of a systemn UML modeling elements in class diagrams– Classes and their structure and behavior– Association, aggregation, dependency, and inheritance relationships– Multiplicity and navigation indicators– Role namesUML Supports Application DevelopmentClassesapplication partitioningBusiness ObjectsRelationshipsBusiness ProcessObjectsUse Caseslarge scale systemScenariosComponentsMicrosoftActiveX/COMMicrosoftORDBMSOracleCORBAOMGUML Conceptsn The UML may be used to:– Display the boundary of a system & its major functions using use cases and actors– Illustrate use case realizations with interaction diagrams– Represent a static structure of a system using class diagrams – Model the behavior of objects with state transition diagrams– Reveal the physical implementation architecture with component & deployment diagrams – Extend your functionality with stereotypes6Copyright © 1997 by Rational Software CorporationActorsn An actor is someone or some thing that must interact with the system under developmentStudentRegistrarProfessorBilling SystemUse Casesn A use case is a pattern of behavior the system exhibits– Each use case is a sequence of related transactions performed by an actor and the system in a dialogue n Actors are examined to determine their needs– Registrar -- maintain the curriculum– Professor -- request roster– Student -- maintain schedule– Billing System -- receive billing information from registrationMaintain ScheduleMaintain Curriculum Request Course RosterDocumenting Use Casesn A flow of events document is created for each use cases– Written from an actor point of viewn Details what the system must provide to the actor when the use cases is executedn Typical contents– How the use case starts and ends– Normal flow of events– Alternate flow of events– Exceptional flow of events7Maintain Curriculum Flow of Eventsn This use case begins when the Registrar logs onto the Registration System and enters his/her password. The system verifies that the password is valid (E-1) and prompts the Registrar to select the current semester or a future semester (E-2). The Registrar enters the desired semester. The system prompts the professor to select the desired activity: ADD, DELETE, REVIEW, or QUIT.n If the activity selected is ADD, the S-1: Add a Course subflow is performed.n If the activity selected is DELETE, the S-2: Delete a Course subflow is performed.n If the activity selected is REVIEW, the S-3: Review Curriculum subflow is performed.n If the activity selected is QUIT, the use case ends. n ...Copyright © 1997 by Rational Software CorporationUse Case Diagramn Use case diagrams are created to visualize the relationships between actors and use casesStudentRegistrarProfessorMaintain ScheduleMaintain CurriculumRequest Course RosterBilling SystemUses and Extends Use Case Relationshipsn As the use cases are documented, other use case relationships may be discovered– A uses relationship shows behavior that is common to one or more use cases– An extends relationship shows optional behavior Register for courses<<uses>>Logon validation<<uses>>Maintain curriculum8Copyright © 1997 by Rational Software CorporationUse Case Realizationsn The use case diagram presents an outside view of the systemn Interaction diagrams describe how use cases are realized as interactions among societies of objectsn Two types of interaction diagrams– Sequence diagrams– Collaboration diagramsSequence Diagramn A sequence diagram displays object interactions arranged in a time sequence: Studentregistration formregistration managermath 1011: fill in info2: submit3: add course(joe, math 01)4: are you open?5: are you open?6: add ( joe)7: add ( joe)math 101 section 1Copyright © 1997 by Rational Software Corporation: Registrarcourse form : CourseFormtheManager : CurriculumManageraCourse : Course1: set course info2: process3: add course4: new courseCollaboration Diagramn A collaboration diagram displays object interactions organized around objects and their links to one another9Copyright © 1997 by Rational Software CorporationClass Diagramsn A class diagram shows the existence of classes and their relationships in the logical view of a systemn UML modeling elements in class diagrams– Classes and their structure and behavior– Association, aggregation, dependency, and inheritance relationships– Multiplicity and navigation indicators– Role namesCopyright © 1997 by Rational Software CorporationClassesn A class is a collection of objects with common structure, common behavior, common relationships and common semanticsn Classes are found by examining the objects in sequence and collaboration diagramn A class is drawn as a rectangle with three compartmentsn Classes