In this SUSS ICT340 End-of-Course Assessment, the whole paper revolves around one Singapore case: an application that the National Environment Agency uses to manage hawker centre stalls, rental agreements, officer inspections and hygiene grades. The five questions take you through requirements analysis, structural and dynamic UML modelling, a state model and a design pattern, with Python code for selected classes.

Question 1

Read the system requirements of the NEA Hawker Centre Inspection application in the Appendix and submit answers to the following:

Question 1a

Formulate a use case diagram to depict the NEA Hawker Centre Inspection application design. Your use case diagram should show the actors, the use cases and their relationships. (12 marks)

Question 1b

The following is an extract of the requirements of the NEA Hawker Centre Inspection application:

“The NEA Hawker Centre Inspection System is a fully automated platform that allows NEA officers to remotely and simultaneously monitor all food stalls in real time. A stall owner may operate multiple food stalls within the same hawker centre. NEA officers are deployed periodically to inspect stalls, and upon completion of each inspection, a hygiene grade may or may not be issued depending on the officer’s discretion.”

Analyse the above extract to identify and explain any TWO (2) ambiguous, incorrect, incomplete or inconsistent inadequacies of the system design as compared to the information given in the Appendix. Note that in your answers, you are not to use imagination to add anything not mentioned in the Appendix. Further, do not include general commentaries in your answer. (4 marks)

Question 2

Develop a structural model for the NEA Hawker Centre Inspection application design by submitting your answers to the following:

Question 2a

Complete the class description by identifying classes, their attributes and any hierarchical relationship(s) that would be required for the application. (15 marks)

Question 2b

Appraise the associations among the classes and hierarchical relationship(s) that would be required for the application. Construct the class association diagram in UML as your answer. Ensure that you do not include any derived or redundant association in your diagram. (14 marks)

Question 3

Analysis on the requirements for the NEA Hawker Centre application gives rise to an updated class diagram which lists all the inspections associated with a food stall, part of which is shown in Figure Q3 of the paper (FoodStall linked to Inspection via hasInspections, and Inspection linked to HygieneGrade via resultsIn). Note that this may not be applicable to Question 2 above.

Assume that the FoodStall class has attribute stallId and the HygieneGrade class has attributes grade and validFrom. Consider the following walkthrough where the application retrieves the grade and validFrom of all hygiene grades associated with a food stall:

Objective: To retrieve a list of hygiene grades and their validity start dates associated with a food stall.
Given: a food stall identifier, stallId

1. Locate the instance, aStall, of FoodStall with the stallId, linked to the orchestrating object via hasStalls.
2. Retrieve all instances of the Inspection objects, linked to aStall via hasInspections.
3. For each instance of the Inspection object, anInspection:
   • 3.1 Retrieve the HygieneGrade object, aHygieneGrade, linked to anInspection via resultsIn.
   • 3.2 Get the attributes grade and validFrom of aHygieneGrade.
   • 3.3 Add grade and validFrom to a list.
4. Return the list.

Question 3a

Develop the dynamic model for the application function by drawing the sequence diagram for the walkthrough where the hygiene grade and validity start date of all hygiene grades associated with the food stall is returned. (14 marks)

Question 3b

Using the Python programming language, implement the method that represents a message that is sent by another object to the object of the following classes in the sequence diagram of Question 3(a):

• i. the orchestrating class (5 marks)
• ii. the FoodStall class (7 marks)

Question 4

Demonstrate the construction of a component in the NEA Hawker Centre Inspection application by submitting your answers to the following: analyse the system requirements in the Appendix and identify the different states of the HygieneGrade object. Draw the state diagram for the HygieneGrade object as it passes through the system. (13 marks)

Question 5

Demonstrate the application of the strategy pattern in the NEA Hawker Centre Inspection application by submitting your answers to the following:

Question 5a

Develop a structural model of the system that uses the strategy pattern by constructing the class association diagram that allows the application to calculate the overall inspection score using different scoring strategies. The scoring strategies used are:

• (i) standard scoring strategy that uses the average of all the scores;
• (ii) weighted scoring strategy that uses a list of weights: [0.5, 0.3, 0.2].

You may assume that there are 3 scores given during an inspection. (6 marks)

Question 5b

Using the Python programming language, implement the concrete classes for the structural model in Question 5(a). (10 marks)

Appendix: NEA Hawker Centre Inspection Application

The National Environment Agency (NEA) oversees hawker centres across Singapore to ensure food safety, hygiene, and operational standards are maintained. Each hawker centre is managed by an appointed operator, who is responsible for the daily operations, rental management, and maintenance of the centre. NEA has commissioned a Hawker Centre Inspection application to monitor stall performance, inspection outcomes and rental arrangements. The operator and NEA officer would log in to this application using a given id and his/her name. Stall owners would sign up with his/her name, NRIC and contact number.

A hawker centre, identified by its name and address, contains many food stalls, each operated by one stall owner. Stall owners sign rental agreements with the operator to lease a stall unit within the hawker centre. Over time, a stall may have multiple rental agreements due to renewals or changes in rental rates.

To maintain food safety standards, NEA assigns NEA officers to conduct regular inspections of food stalls. During an inspection, an officer assesses the stall’s cleanliness and food handling practices, records several scores, and provides remarks. Based on the inspection results, a hygiene grade (such as A, B, C, or D) is assigned to the stall. Hygiene grades are valid for a fixed period, and a stall may receive multiple hygiene grades over time.

Stall owners can log into the application to view their inspection history and current hygiene grade. Operators use the application to manage rental arrangements for all stalls in their hawker centre. NEA officers use the application to schedule and record inspections, and to assign hygiene grades.

Both the operator and NEA use the application to monitor stall performance and inspection outcomes. By analysing inspection scores over time, stakeholders can make informed decisions to improve hygiene standards and overall hawker centre operations.

Submission Notes

• Individual work; include the course code, ECA title, SUSS PI number, name and submission date.
• Submit through Canvas by Monday, 02 November 2026, 12 noon; late work follows the ECA marks deduction scheme (10 marks per 24-hour block after the grace period).
• Reference all sources in APA style; the submission is screened for plagiarism and collusion.