Object-Oriented Software Development with UML - UNU-IIST ...

124 QuestionsStore1address:Addressname:TextaddSale()1Houses1UsesLooks-in11ProductCatalogspecification()loadProdSpecs()Contains1 1..*ProductSpecificationdescription:Textprice:Quantityupc:UPC1Describes*11SaleSalesLineItemPOSTdate:datetime:TimeisComplete:BooleanContains1 1..*quantity:Integersubtotal()endSale()enterItem()makePaymentbecomeComplete()makeLineItem()makePayment()total()*1PaymentLogs-completedPaid-by1amount:QuantityFigure 7.42: Design diagram with association and navigabilityWe do not show the messageÒÏ Æ9À§ÈXÆÖ¤× sent to a class as a method of the class, because its interpretation¾is dependent on programming languages.¾Accessing methods are those which retrieve (accessor method) or set (mutator methods) attributes. Itis a common idiom to have an accessor and mutator for each attribute, and to declare all attributesprivate (to enforce encapsulation). These methods are also usually excluded from the class diagrambecause of the high noise-to-value ratio they generate.7.4 Questions1. What is the difference between *msg(), *[true] msg(), and [true] msg() in a collaboration diagram?2. You might think it would be more obvious just to number all the messages in a collaboration diagramusing êå9ð©åÊÊÊBå rather than using the nested scheme. What diference would it make? Can youconstruct a situation in which it would be ambiguous?3. We have said that the UML creation message is denoted by Ò Ï Æ:À§ÈXÆÖ¤× (sometimes with parameters)with the newly created object labelled with Þ›ÞñÅ+Æòàâ›â . In a collaboration diagram, objects mybe deleted/destroyed as wel as created. The UML notation for a message destroying an object isÑ ÆWÂWÈ Ï;Ð Í+Ö¤× with the deleted objects labelled with ÞÞ Ñ ÆWÂDÈ Ï¦Ð Í¥Æ Ñ ââ .Can you think of a situation when we need to show in a collaboration diagram an object beingdestroyed?4. Develop a collaboration diagram in which:Report No. 259, July 2002UNU/IIST, P.O. Box 3058, Macau