🛒 Lab Exercise: IO Operations & Serialization (POS System)

📋 Overview

• Topic: IO Operations and Serialization
• Type: Group Task
• Scenario: You have been hired to develop a Point of Sales (POS) system for the "Super-Saving" supermarket chain.

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🏬 The Scenario & Functionality

1. The Billing Process 🧾

• Input: The cashier enters an item code and the amount/quantity.
• Data Retrieval: The system fetches details (price, weight/size, manufacturing/expiry dates, manufacturer) from a CSV database.
• Discounts: Items are occasionally given discounts ranging from 0% to 75%.
• The Final Bill: The system processes the list and produces a bill containing:
  • Cashier Name & Branch
  • Customer Name (if registered)
  • Item List (Unit price, Quantity, Discount, Net price)
  • Totals (Total Discount, Total Cost)
  • Timestamp: Date and time the bill was printed.
• Output Format: The final bill for the customer must be saved as a PDF file.

2. Handling "Pending" Bills ⏳

• The Problem: A customer might forget to weigh an item (e.g., vegetables) after half their items are already scanned.
• The Solution: The cashier must be able to save the current bill as "pending" and proceed to check out other customers while the first customer retrieves their missing item.
  • Hint: This usually requires object serialization to save the temporary state of the bill.

3. Management Reporting 📊

• Analysis: The system must analyze bills to generate a total revenue report for a specific date range.
• Delivery: This report must be automatically emailed to the sales team at salesteam@supersaving.lk.

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🛠️ Your Tasks

Task 1: Requirements Analysis 📝

Identify all Functional and Non-Functional requirements for the POS system based on the scenario above.

Task 2: Data Format Strategy 💾

Decide on the best file formats to use for saving data for each requirement (e.g., What format is best for a printable bill? What format is best for a temporary pending bill object?).

Task 3: Implementation (Java) ☕

Design and implement the solution using Object-Oriented Programming principles.

⚠️ Critical Implementation Constraints:

1. Single File Only: You must include all classes in a single file. (Note: This is generally bad practice, but required here for grading).
2. Naming Convention: The class containing the main method must be named: SuperSaverPOSGroup_<<Your Group Name>>.
3. Documentation (Javadoc):
   • Top of File: Include a Javadoc comment listing your identified requirements and explaining the overall program functionality.
   • Code Level: Every class and method must have a Javadoc comment explaining its functionality and parameters.
4. Readability: Ensure proper variable naming and comments throughout.

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📤 Submission Guidelines

• File Format: Save your Java code as a PDF file.
• Rename: Rename the file with your group name.
• Plagiarism Check: This is a Turnitin assignment.
  • Similarity must be less than 20%.
  • Submissions with higher similarity will not be graded.