Communication diagrams - School of Engineering and Information

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Transcript Communication diagrams - School of Engineering and Information

ZEIT2301 Design of Information Systems Interaction Design: Communication Diagrams School of Engineering and Information Technology UNSW@ADFA Dr Kathryn Merrick

Topic 07: Interaction Design  Objectives  To understand the notation, rules and style guidelines for creating communication diagrams (previously known as collaboration diagrams)  To understand one technique for identifying potential interactions between objects is a

CRUD analysis

.

Reference: Text Ch 7 2

Communication Diagrams

Communication diagram

– is a behavioural diagram that shows message passing relationships between objects & actors.  It is equivalent to a sequence diagram, but   Communication diagram - emphasizes the flow of messages through a set of objects, Sequence diagram – emphasizes the time ordering of messages  The analyst/designer may choose either or both.

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Communication Diagrams

 Elements of a communication diagram: 

Actors

&

objects

  

Associations

&

messages

– messages are labels on associations Sequence – messages are assigned a sequence number Conditions - messages can be conditional Session 2, 2010 4

Communication Diagram Syntax Session 2, 2010 5

Communication Diagram

Session 2, 2010 6

Communication Diagram - Rent Movie

:

Rented Items 7 print invoice() 1 find_customer() 3 enter_movie() 5 rent(movie) 6 add(customer, movies) 8 generateRentalTotal() 2 search(CustId)

:

Check-out Manager

:

Employee

:

Customer 4 searchBarcode()

:

Inventory Message Object 7

CRUD: an analysis technique

 One technique for identifying potential interactions between objects is a

CRUD analysis

.

 

CRUD

stands  

C

: create

R

: read (or reference)  

U

: update

D

: delete Use a CRUD matrix … 8

Sample CRUD Matrix

An object of the receptionist class needs to be able to Create, Read, Update and Delete objects of the Patient class.

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Summary

 

Behavioural Modelling State Machine diagrams

– shows the different states that an object of a single class passes through during its life in response to events.

 Can also be used at a higher level to explore the complex behaviour of a system or component, particularly real-time systems.

  

Interaction Diagrams Sequence diagram

the messages that pass between them. Emphasis on the time ordering of messages sent.

– illustrates the objects that participate in a use case and

Communication diagram

– equivalent to sequence diagrams (i.e. objects & messages), but emphasis on the flow of control between objects.

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