Modelling systems with object.

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Modelling systems with object
OBJECT ORIENTED MODELLING-CRC METHOD
Steps in object oriented modelling
1) Find objects and their classes
2) Determine responsibilities of each object
3) State responsibilities, that is, actions. It can carry out on its own using its knowledge
4) Determine objects with whom they collaborate.
5) State contracts each object assigns to its collaborators
6) A collaborator either performs a requested action or gives information
7) Document each class – its responsibilities,its collaborators and their responsibilities
8) Develop an object interaction/collaboration graph
CRC TEAM IDEA
CRC TEAM : user's representative
System analyst(s)
project coordinator
RESPONSIBILITY : Identify objects
Specify responsibility
Specify collaborators and their
responsibilities
Prepare a card for each class called class index cards
CRC METHODOLOGY
1. Make CRC Card for each class
CRC CARD
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Develop a graph to show interaction between classes
CRC MODEL – EXAMPLE1
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REFERENCES
1. Most of the material in this module has been taken from the book “Analysis and Design of Information Systems”, 2nd Edition, V.Rajaraman, Prentice Hall of India, New Delhi, 2003. Chapter 13, Object Oriented System Modelling (pp.180-199)
2. There are several standard books on object oriented modeling for those who want to study deeper. Some of these are:
(i) I.Jacobson et.al “Object Oriented Software Engineering”, Pearson Education Asia, 1998
(ii) David Colemen et.al “Object Oriented Development”, Prentice Hall, Inc., N.J., WA,1999
(iii) J.Rumbaugh et.al “Object Oriented Design and Applications”, Benjamin Cumming, U.S.A., 1991











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