Assignment 2 - Modelling: IMAT5205 Systems Analysis and Design

This document presents a comprehensive solution to a Systems Analysis and Design assignment (IMAT5205), focusing on modeling techniques. The solution encompasses various UML diagrams, including class diagrams, communication diagrams, and sequence diagrams, to visually represent system structure and interactions. Design decisions are clearly articulated, providing insights into the rationale behind specific modeling choices. The document also evaluates the use of CASE tools in the software development lifecycle, emphasizing their role in automating processes and ensuring software quality. The solution is well-structured, with clear explanations, diagrams, and references to support the analysis and design processes. This assignment demonstrates an understanding of system analysis principles and the practical application of UML for effective system modeling. The document covers topics such as the analysis class diagram, decisions, communication diagram, sequence diagram, design decisions, and evaluation.

COVER PAGE

Contents
Part 1...........................................................................................................................................................3
class diagram...........................................................................................................................................3
Decisions.................................................................................................................................................3
Communication Diagram.............................................................................................................................3
Design decisions......................................................................................................................................4
Sequence diagram.......................................................................................................................................4
Design decisions......................................................................................................................................5
Evaluation....................................................................................................................................................6
References...................................................................................................................................................6

Part 1
class diagram
Class diagrams are UML diagrams used to model the static structure and the dynamic structure of a
system. To model a system using an analysis class diagram objects making up the system have to be
identified (Ambler, 2014). Each object can be modelled as a class to make up the class diagram. A class is
identified by attributes which become variables and behaviors which become methods when the class is
modelled. Classes are related though different techniques including inheritance between parent classes
and child classes, aggregation and composition. Class diagrams are important while modelling a system
using UML (microTOOL, 2018).
Class diagrams are very important in system analysis because they are the heart of UML. Class diagrams
are modelled on the basis of object orientation thus can be used in different phases of a project. In the
analysis stage of a project, class diagrams act as the domain model by creating a representation of the
real world. During the design and implementation phase, class diagrams can be applied for generation of
source code.
Figure 1: Analysis Class diagram
Decisions
 A tour has one or more itineraries. An itinerary can be an event that are held in different stages
of the tour or in different venues that visited during the tour.
 Each tour is assigned or more drivers. A tour cannot happen without a driver.
Communication Diagram
As discussed in the section above, a system can be modelled using objects which are represented as
classes. A communication diagram models a system by showing the interactions that exist between
objects of a system. The communication can be in form of messages which are relayed in sequences

between objects. By showing the objects making up a system and the interactions between the objects,
communication diagrams are able to model both the static and dynamic behavior of a system
(Fakhroutdinov, 2016).
Importance of communication diagrams;
 The help to model exchange of messages between objects of a system thus showing how
different use cases of the system are achieved.
 They are used in modelling of mechanisms within the system’s architectural design.
 They are used in capturing of interactions showing the exchange of messages between objects.
 Model different scenarios within operations or use cases that involve collaboration of different
interactions and objects in a system.
Communication diagram;
Figure 2: Communication diagram
Design decisions
 While adding a new tour, the leader codes are prepopulated in the interface such that the user
does not have to write the leader code manually instead they are just supposed to select their
desired leader codes.
 When the user is adding a new tour, all drivers are prepopulated thus the clerical assistant does
not have to manually input the driver identifications.
Sequence diagram
Sequence diagrams are UML diagrams used to show interactions between classes making up a system.
The periodic exchange of messages between classes forms the interactions between classes. Sequence
diagrams are very important in system analysis and design as they give a visual of scenarios that are
taking place at runtime in order thus can be used to validate a system. Validation based on the
interactions helps to view the behavior of the system and to show the responsibilities of different
classes within the system (Rohitha, 2011)

Add new tour use case sequence diagram
Figure 3: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Sequence diagram
Design decisions
 When the user is adding a new tour, the leader codes are prepopulated in the interface such
that the user does not have to write the leader code manually instead they are just supposed to
select their desired leader codes.
 When the user is adding a new tour, all drivers are prepopulated thus the clerical assistant does
not have to manually type the driver IDs.

Evaluation
Case tools are tools used to automate software development. They ensure quality of a software by
making the development process easy and reducing the cost and the time used to develop a software.
In a project life cycle, CASE tools can be used in many stages. In the early stages of the project life cycle,
they are used in identification of functional requirements and actors by use of use case diagrams. Class
diagrams are then used to show the domain model of the system by showing the objects modelled from
reality and then later on converted and used to generate code (Krishnamurthy, G,A). Different CASE
tools are used at different stages of the project life cycle. By using the CASE tools systematically, the final
system is able to meet all requirements and achieves a high-level design thus the final software that is
released is able to meet all requirements.
References
Ambler, S.W., 2014. UML 2 Class Diagrams: An Agile Introduction. Agile Modelling. Available at:
http://www.agilemodeling.com/artifacts/classDiagram.htm [Accessed January 6, 2020].
Fakhroutdinov, K. (2016). UML communication diagrams overview - graphical notations for lifeline,
message, etc.. [online] Uml-diagrams.org. Available at: https://www.uml-diagrams.org/communication-
diagrams.html [Accessed 6 Jan. 2020].
Krishnamurthy, G.A., CASE Tools. umsl. Available at:
http://www.umsl.edu/~sauterv/analysis/F08papers/View.html [Accessed January 6, 2020].
Rohitha, 2011. The Basics & the Purpose of Sequence Diagrams ~ Part 1. creately blog. Available at:
http://creately.com/blog/diagrams/the-basics-the-purpose-of-sequence-diagrams-part-1/ [Accessed
January 6, 2020].
microTOOL. (2018). What is a class diagram? – Knowledge Base. [online] Available at:
https://www.microtool.de/en/knowledge-base/what-is-a-class-diagram/ [Accessed 6 Jan. 2020].