Imat5205 Systems Analysis And Design Assessment Answers

Communication Diagram

a)In your own words, briefly describe what is modelled in a Communication Diagram, and how Communication Diagrams can be useful in systems analysis and design

b)Draw a Communication Diagram for the use case ‘Record New Tour’, using the Use Case description given. This should include all control, boundary and entity objects involved in the scenario and sufficient detail of the messages to show that the interaction is feasible and would meet the system requirements. Your diagram should be drawn using the Enterprise Architect software, and copied and inserted as a picture into your document.

c)Write a brief summary of the decisions made whilst drawing the diagram, and your reasons for making them.

Part 2. Sequence Diagram

a)In your own words, briefly describe what is modelled in a Sequence Diagram, and how Sequence Diagrams can be useful in systems analysis and design

b)Draw a Sequence Diagram for the use case ‘Record New Tour’.  This should include all control, boundary and entity objects involved in the scenario and the sequence of interactions that take place in order to meet the system requirements. Your diagram should be drawn using the Enterprise Architect software, and copied and inserted as a picture into your document.

c)Write a brief summary of the decisions made whilst drawing the diagram, and your reasons for making them.

Part 3. Evaluation

Enterprise Architect is a CASE tool. In your own words and using examples, briefly describe what a CASE tool offers during analysis of the World Wide Tours scenario, and what tasks the CASE tool supports. Give your own evaluation of how the role of an analyst/designer is supported by a CASE tool.  Discuss how UML modelling supports the analyst/designer.

University policies on late submission of coursework and plagiarism will be strictly adhered to for this assignment.

This is an individual assignment.  This part of the coursework represents 60% of the module mark.

The marking scheme indicates how marks are given for each aspect of the work.

Learning Outcomes (from module template)

1  Have a comprehensive understanding of the role of the systems analyst/ designer, the context in which the systems development activity takes place and the professional standards that are applied to the activity.

2 Apply up to date structured techniques to produce analysis and/or design models for a given case study problem

Answer:

An analysis class diagram is a system modelling tool that aids in the modelling of the static structure of a given system (Buede and Miller, 2016). Class diagrams play a critical role in system analysis and design, as they help in decomposing a design problem into understandable units; by representing classes that makes up a system, operations of the classes, attributes , objects and there inter-relationships (Buede and Miller, 2016). Analysis Class Diagrams helps a system analyst in exploring the domain concepts and analyze requirements of a system.  

An analysis class diagram is a visual representation in the Unified Modeling Language (UML) used during the early stages of software system development. It focuses on modeling the essential concepts, classes, and their relationships in the problem domain without delving into implementation details. Analysis class diagrams are a key component of the requirements analysis phase and serve as a foundation for designing the system.

Here are the key elements typically found in an analysis class diagram:

1. Classes: Each class represents a fundamental entity or concept within the problem domain. For example, in a library management system, you might have classes like "Book," "Library Member," and "Transaction."

2. Attributes: Classes have attributes that describe their properties or characteristics. These are often depicted as name-value pairs, such as "Book Title" and "Author" for the "Book" class.

3. Associations: Lines connecting classes indicate relationships between them. Associations can be one-to-one, one-to-many, or many-to-many, and they convey how instances of classes interact with each other.

4. Multiplicity: This notation indicates the number of instances involved in a particular association. For instance, a "Library Member" might have a one-to-many association with "Transaction," meaning one member can have multiple transactions.

5. Roles: Roles describe the participation of classes in an association. For example, in an association between "Book" and "Library Member," "Lender" could be a role for "Library Member" and "Borrowed Book" a role for "Book."

6. Operations: These represent the behaviors or methods that a class can perform, although they are not usually specified in detail at the analysis stage.

Analysis class diagrams help stakeholders and developers understand the structure and relationships within the problem domain. They serve as a basis for creating design class diagrams and, eventually, implementing the system.

Analysis Class Diagram

Summary of the decisions made whilst drawing the diagram

While drawing the analysis class diagram, the biggest handle was whether to include the SystemUI class, which models the boundary between the users and the system. The decision to include SystemUI was arrived after considering the importance of having a boundary object. The obvious entities from the given use case description were; Tour, Driver and Tour Leader. As such I had to make a decision on what control object to include. The inclusion of the System class was therefore necessitated by the need to have a control object. The decision to include a relationship between a Tour and a Driver was motivated by the fact that one Tour could have more than one driver assigned to it. As such, the relationship needed some attributes. We assume that a Tour Leader has an attribute name, although only code is mentioned.

Communication Diagram

A communication diagram models the interaction between parts or objects of a given system. The interaction is represented by use of sequenced messages that follows no particular order of flow (Dennis and Wixom, 2015). Communication diagrams helps model implied relationships between classes of the system being designed (Dennis and Wixom, 2015).

Decisions made whilst drawing the communication diagram

To come up with the communication diagram, I had to decide on how to translate the flow of the use case description into interaction between the various entities of the system. The decision to include the five objects in the communication diagram was motivated by the fact that the five objects are the main constituents of this system. The communication between the objects was modeled according to the steps identified that facilitates the accomplishment of the functions of the system.

A secure diagram models a sequenced and ordered interaction between objects. It is almost similar to a communication diagram, except that a sequence diagram arranges the communication with a time sequence of the interaction (Abrahao,Gravino,Insfran,Scanniello and Tortora, 2013). The diagram represents the interaction in a time sequenced order. It includes classes and objects involves in the interaction and the sequence of message exchanges between them.

Decisions made whilst drawing the diagram

The main decision whilst drawing the sequence diagram was which objects are to interact, and the sequence of the interaction. The modeled interaction steps were included in consideration for the interaction between the objects, and the sequence of the interaction.

Evaluation

A use CASE tool such as Enterprise Architect plays a vital role in any system analysis case, and the World Wide Tours scenario in particular. In the analysis of the case at hand, the CASE tool makes it possible for an analyst to process various analysis and design diagrams (Arman, 2013). The CASE tools offer a wide range of tools that enables an analyst to edit and update many design options. Use of CASE tools makes the analysis and design process very easy as the feature reach tools facilitates quick editing of the diagrams. The tools also help in checking design errors, testing case generation and improvement of designs (Osman and Chaudron, 2014).

The role of an analyst and designer is supported by a CASE tool in that the tool provides a platform and means of putting across analysis and design diagrams. The alternative to use of CASE tool would be manual drawing –pencil and paper- which is not only cumbersome, but inflexible and time taking. With a CASE tool, most of the work of an analyst is automated, such as error checking (Valacich,George and Hoffer,2015). A designer can therefore concentrate on the core task of analyzing requirements, translating the requirements into a design and refining the designs to optimize the system. The tool provides a form of automated assistance to the designer, with the aim of reducing the analysis and design time, translating to a reduction in cost and quality enhancement of the systems developed (Osman and Chaudron, 2014). As such, CASE tools increases the productivity of designers, enhances maintenance of the developed systems and improves quality, making the work of analysis and designers to be both easier and enjoyable (Osman and Chaudron, 2014). 

The use of CASE tools results in the production of UML diagrams. UML diagrams are blueprints of the system being designed; they assist the work of an analyst and designer by enabling effective communication between developers and system users (Larman, 2015). Use of UML helps the designers communicate the design of the system to the IT and business teams, helping them visualize the requirements of a system and processes that makes up the entire system. The work of an analyst is therefore made easier as UML gives them a 360 degree visualization of the system, thus easing the process of identifying major issues in the design and development process (Rosenblatt, 2013).

References

Arman, N., 2013. Towards e-case tools for software engineering.

Abrahao, S., Gravino, C., Insfran, E., Scanniello, G. and Tortora, G., 2013. Assessing the effectiveness of sequence diagrams in the comprehension of functional requirements: Results from a family of five experiments. IEEE Transactions on Software Engineering, 39(3), pp.327-342.

Buede, D.M. and Miller, W.D., 2016. The engineering design of systems: models and methods. John Wiley & Sons.

Dennis, A., Wixom, B.H. and Tegarden, D., 2015. Systems analysis and design: An object-oriented approach with UML. John Wiley & Sons.

Larman, C., 2015. Applying UML and Patterns: An Introduction to object-oriented Analysis and Design and iterative development”, Pearson Education, 2005.

Osman, H. and Chaudron, M.R., 2014. Correctness and Completeness of CASE Tools in Reverse Engineering Source Code into UML Model. GSTF Journal on Computing (JoC), 2(1).

Rosenblatt, H.J., 2013. Systems analysis and design. Cengage Learning.

Valacich, J.S., George, J.F. and Hoffer, J.A., 2015. Essentials of systems analysis and design. Pearson Education.