Question

A shop specialising in household paint products has approached you (an application developer) for your services. they want you to develop an application they will use in their shop to estimate the amount of paint that customers would need to purchase when they supply the dimensions of their houses. to develop this application, you will work on the following assumptions: • a house is a three-dimensional structure (the dimensions are length, width and height) • a tin of paint covers about 10 square meters of wall space. create an application using java that prompts the user for a rectangular room's length, width, and height. pass these three parameters to a method that does the following: • calculate the room's wall area and display it inside a label when a button is clicked. • passes the calculated wall area to another method that calculates and returns the number of tins of paint needed. • displays the number of tins needed in a label. this must happen at the click of a button. • compute the paint price given that a tin of paint costs r30 assuming that any fraction of paint is bought at the full price of a tin. the total cost of the paint should be displayed on a label when a button is clicked. • the system (application) should calculate and display the amount of value added tax charged, and the total cost of the paint after value added tax should be displayed. • lastly, the application should capture the amount tendered to the cashier and calculate and display the change.

Answer 1

Below is an example of a Java program that does the above function.

java

import java.util.Scanner;

public class PaintEstimationApp {

// Constants

static final double PAINT_COVERAGE_PER_TIN = 10.0; // in square meters

static final double PAINT_PRICE_PER_TIN = 30.0; // in currency (e.g., rands)

// Calculate wall area

static double calculateWallArea(double length, double width, double height) {

return 2 * (length * height + width * height);

}

// Calculate number of tins needed

static int calculateTinsNeeded(double wallArea) {

return (int) Math.ceil(wallArea / PAINT_COVERAGE_PER_TIN);

}

// Calculate total cost with VAT

static double calculateTotalCost(int numTins) {

double totalCost = numTins * PAINT_PRICE_PER_TIN;

double vat = 0.15 * totalCost; // Assuming a 15% VAT rate

return totalCost + vat;

}

public static void main(String[] args) {

Scanner scanner = new Scanner(System.in);

// Get user input for room dimensions

System.out.print("Enter room length (m): ");

double length = scanner.nextDouble();

System.out.print("Enter room width (m): ");

double width = scanner.nextDouble();

System.out.print("Enter room height (m): ");

double height = scanner.nextDouble();

// Calculate wall area

double wallArea = calculateWallArea(length, width, height);

// Calculate number of tins needed

int numTins = calculateTinsNeeded(wallArea);

// Calculate total cost with VAT

double totalCost = calculateTotalCost(numTins);

// Display results

System.out.println("Wall Area: " + wallArea + " square meters");

System.out.println("Number of Tins Needed: " + numTins);

System.out.println("Total Cost (incl. VAT): " + totalCost);

// Additional functionality for capturing amount tendered and calculating change

System.out.print("Enter amount tendered: ");

double amountTendered = scanner.nextDouble();

// Calculate change

double change = amountTendered - totalCost;

// Display change

System.out.println("Change: " + change);

scanner.close();

}

}

What is the code for the application?

The above program figures out how much paint and money you need to paint a wall. Then it takes the money given and figures out the difference.

Therefore, one need to make this program even better by adding it to a graphic user interface (GUI) application to match with what one's shop needs.