Slides Part 2 (OOA, pages 1-128, pdf, 4 slides per page)

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FUSION NOTATION Operation = 〈Name〉 Description = 〈Informal description〉 Reads = 〈Input〉 Changes = 〈Objects/Attributes/Associations, that might be changed 〉 Sends = 〈Output events〉 Pre = 〈Precondition〉 Post = 〈Postcondition〉 Sends Events that can be but do not have to be created. Must contain all output events occurring in the scenarios. Receiving actor is stated, e.g. Employee: {give money(amount), no cover} 69 Pre refers to the system state before calling the system operation and the supplied values. The effect of system operation as given by postcondition is only specified if the precondition is fulfilled. The precondition should be established by the sequences of events specified in the scenarios and in the life-cycle model. 71 COMPONENTS OF AN OPERATION SCHEMA Reads Objects/Attributes/Associations, whose state or value can be read but not changed. Keyword supplied for arguments that are from an actor (from exterior) Inputs that are not ”‘supplied”’ come from the internal state. Changes The concerned values can be read as well as changed but need not be changed. Keyword new for objects that are created by the system operation. Keyword delete for objects that are deleted by the system operation. Reads and Changes clauses must be disjoint! Post Relation (expressed as predicate) between pre-state and inputs on the one hand and post-state and outputs on the other hand. Variables of the post-state are decorated with ”‘ ′ ”’. 70 Predicate is sent{event} describes that event is sent to the actor given in the sends-clause as an effect of the system operation. No program! Only the effect is specified but not how it is achieved!!! 72
Excursion: Design by Contract What are preconditions and postconditions good EXAMPLE I want to travel from Berlin to Duisburg. for? Commitments Advantages Passenger Pay ticket getting to Duisburg Traffic provider 73 Be there at departure time must keep precondition Has advantages from the postcondition Must take the passenger to Duisburg receives the price for the ticket; does not have to take passengers who have not paid or did not arrive in time Must guarantee postcond. Can assume precondition 75 SOURCE Bertrand Meyer Object-Oriented Software Construction Prentice Hall 1988 (1. Aufl.), 1997 (2. Aufl.) online see: http://archive.eiffel.com/doc/manuals/technology/contract/page.html CONTRACTS IN DAILY LIFE ➠ Contractual partners are clients and sellers or service providers. ➠ Both expect advantages from the contract and are willing to make a commitment. ADVANTAGES OF EXPLICIT CONTRACTS Meyer: 74 A contract document protects both the client, by specifying how much should be done, and the supplier, by stating that the supplier is not liable for failing to carry out tasks outside of the specified scope. APPLICATION TO SOFTWARE A contract is a formal agreement between a system / a class and its actors / clients. It specifies the rights and duties for both sides. 76
Page 1 and 2: LITERATURE The Fusion Method using
Page 3 and 4: 5. System class model Borderline be
Page 5 and 6: MEANING OF THE CLASS DIAGRAM ➠ Ea
Page 7 and 8: STRUCTURING CLASS MODELS In general
Page 9 and 10: ACTORS ➠ are outside of the syste
Page 11 and 12: ➠ extend-relation extension point
Page 13 and 14: EXAMPLE: OPENING AN ACCOUNT • Nor
Page 15 and 16: PATTERN FOR MODELING “” REMARKS
Page 17: OBJECT-ORIENTED ANALYSIS ➠ Class
Page 21 and 22: APPLICATION OF THE DESIGN-BY-CONTRA
Page 23 and 24: SCHUFA QUERY REMARKS sd SchufaQuery
Page 25 and 26: USE CASE “PREPARE APPLICATION/CON
Page 27 and 28: Operation = application not accepte
Page 29 and 30: LIFE-CYCLE EXPRESSIONS The Life-Cyc
Page 31 and 32: Canc = cancel contract;#confirm can

Slides Part 2 (OOA, pages 1-128, pdf, 4 slides per page)

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