Essential use cases and responsibility in object-oriented development

Essential Use Cases and Responsibility in Object-Oriented Development Robert Biddle, James Noble, Ewan Tempero School of Mathematical and Computing Sciences Victoria University of Wellington Wellington, New Zealand (robert,kjx,ewan)@mcs.vuw.ac.nz ABSTRACT



  


 
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ESSENTIAL USE CASES borrowingBook

returningBook

User Intention

System Responsibility

User Intention

identify self

System Responsibility

identify self verify borrower id

verify borrower id

identify book

identify book verify that book may be borrowed record book as issued to borrower

CRC CARDS ITERATION 1

record book as returned by borrower

System Object verify borrower id verify that book may be borrowed record book as issued to borrower record book as returned by borrower

ITERATION 2 Library System

Borrower

verify borrower id

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issue book to borrower

Book

know all borrowers know all books

Book verify that I may be borrowed issue myself to borrower return myself

ITERATION 3 Library System

Catalogue

verify borrower id

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Book

issue book to borrower know all borrowers

Book Catalogue

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PATTERNS OF USE CASES

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5.1 Some example use case patterns

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