Question

This is my code so far for the assignment. I am stuck on the last 3 tasks which are task#3, task#4 and task#5.

Task #3 String Comparisons

In

checkForDiscount()

method of the driver:

1. Figure out if there is a discount of $2 on this order, due to the customer's name being

either Mike or Diane

2. Return either 2 or 0 as the discount to the cost of the pizza

3. Compile, debug, and run. You should now be able to test all the crust types.

Run your program multiple times with different user names, including Mike and Diane.

Task #4 Arithmetic Calculations

In the calculateTax(double cost) method of the driver:

1. Compute the tax by multiplying the constant TAX_Rate by the cost (passed as a

parameter to the method).

2. Return the tax (back to main)

Task #5 Formatting Numbers

In the displayFinalPrice(double cost, double tax) method of the driver:

1. Instantiate the DecimalFormat class (make sure you have imported java.text.DecimalFormat).

Then, using JOptionPane, display the cost, tax, and grand total of the order, applying the

DecimalFormat object.

Hint:

To use DecimalFormat, you must first instantiate it like this:

DecimalFormat aFormat = new DecimalFormat("$##0.00");

Then, to format a variable named cost, you would use the following statement:

aFormat.format(cost)

Note that the DecimalFormat object that always shows 2 decimal places.

2. Compile, debug, and run. Your output should be completely correct at this time, and numeric

output should look like money.

public static double checkForDiscount()
{
double discount = 0;
//return a discount if user is eligible
//Task #3: Figure out whether to return 0 or $2, depending on whether the customer's name is either Mike or Diana
  
  
  
  
return discount;
}
  
  
/**
* add comments about what this method does, what it receives as a parameter, and what value it returns.
* @param cost
* @return
*/
public static double calculateTax(double cost)
{
final double TAX_RATE = .08; //sales tax rate   
double tax = 0;
  
//Task #4: Calculate tax by multiplying tax_rate by parameter
  
  
return tax;
}
  
  
/**
* add comments about what this method does, what it receives as parameters.
* @param cost
* @param tax
*/
public static void displayFinalPrice(double cost, double tax)
{
//ALL MONEY OUTPUT APPEARS WITH 2 DECIMAL PLACES, using the DecimalFormat class defined at the beginning of this method.
//calculate and display tax and total cost
  
DecimalFormat aFormat = new DecimalFormat("$##0.00");
  
//Task #5: Using JOptionPane, display "The cost of your order is: " (use the DecimalFormat object)
// "The tax is: " (use the DecimalFormat object)
// "The total due is: " (use the DecimalFormat object)
// "Your order will be ready for pick-up in 30 minutes."

}
  
}

Answer 1

In case of any query do comment. Please rate answer as well.

Code:

import javax.swing.*;
import java.util.*;
import java.text.DecimalFormat;

public class Test
{

    public static void main(String[] args) {
  
//Let us assume the cost is $25.
double cost = 25.00;
double tax =0.0;
cost = cost - checkForDiscount();
tax = calculateTax(cost);
  
displayFinalPrice(cost,tax);
  
   }

public static double checkForDiscount()
{
double discount = 0;
//return a discount if user is eligible
//Task #3: Figure out whether to return 0 or $2, depending on whether the customer's name is either Mike or Diana

/*
you did not mention the full structure of your class and other things so for testing purpose I am taking input from the user for name.
It is assumed that customer name is already available for you in checkFOrDiscount Method, you can remove these lines to get customer name
*/
String customerName;
Scanner scnr = new Scanner(System.in);
System.out.println("Enter the customer name");
customerName = scnr.next();

if(customerName.equals("Mike") || customerName.equals("Diane"))
discount =2.0;


return discount;
}

/**
* Compute the tax by multiplying the constant TAX_Rate by the cost (passed as aparameter to the method).
* @param cost
* @return cost mulitplied by constant tax rate
*/
public static double calculateTax(double cost)
{
final double TAX_RATE = .08; //sales tax rate   
double tax = 0;
  
//Task #4: Calculate tax by multiplying tax_rate by parameter
tax = cost * TAX_RATE;
  
return tax;
}
  
  
/**
* using JOptionPane, display the cost, tax, and grand total of the order, applying the DecimalFormat object.
* @param cost
* @param tax
*/
public static void displayFinalPrice(double cost, double tax)
{
//ALL MONEY OUTPUT APPEARS WITH 2 DECIMAL PLACES, using the DecimalFormat class defined at the beginning of this method.
//calculate and display tax and total cost
  
DecimalFormat aFormat = new DecimalFormat("$##0.00");
String output;
  
//Task #5: Using JOptionPane, display "The cost of your order is: " (use the DecimalFormat object)
// "The tax is: " (use the DecimalFormat object)
// "The total due is: " (use the DecimalFormat object)
// "Your order will be ready for pick-up in 30 minutes."
  
output = "The cost of your order is: " + aFormat.format(cost) + "\n";
output = output + "The tax is: " + aFormat.format(tax) + "\n";
output = output + "The total due is: " + aFormat.format(cost + tax) + "\n";
output = output + "Your order will be ready for pick-up in 30 minutes.";
  
JFrame f = new JFrame();      
JOptionPane.showMessageDialog(f,output);

  
}
}

====================Screen shot of the code========

Output: