Question

In Java write an application that calculates total retail values for 5 different shoes entered by the user.

Shoe 1 $15.50
Shoe 2 $27.30
Shoe 3 $34.50
Shoe 4 $42.11
Shoe 5 $54.25

Application must read shoe number and quantity sold for each product stdin, compute the total value of that sale, and add the value of that sale to a grand total for that shoe. After all data has been entered, display the total value of each of the five shoe items. Must have two classes, must use a switch structure to which shoes sales to update, must use a sentinel controlled loop to determine when the program should stop looping and display result.

Methods
One 1 argument constructor, getters and setters for each field, and updateTotalSales method(uses one parameter representing quantity sold and does not return a value) . must use getter and setter methods t access the fields do not access them directly.

Sample run
Shoe number: 2
Quantity sold: 4
Shoe number: 1
Quantity sold: 3
Shoe Number: 5
Quantity sold: 2
Shoe number: 1
Quantity sold: 2
Shoe number: 5
Quantity sold: 3
Shoe Number: 4
Quantity sold: 2
Shoe Number: 0

Total Sales
Shoe 1 : $31.00
Shoe 2: $109.20
Shoe 3: $0
Shoe 4: $84.22
Shoe 5: $271.25

Answer 1

Hi,

Hope you are doing fine. I have coded the above question in java and have adhered to all the requirements asked in the question. However, there is one error in the Sample output provided in the question. As per the logic, the cost of all shoes except shoe number 1 is printed accurately. The cost of shoe number 1 must be $77.5 and not $31.00. Here is the logic, if we look at the input entered we see that number of shoe number 1 purchased are 3+2=5. And cost would be 15.50 * 5 =77.5. I have clearly explained the program using comments that have been highlighted in bold.

Program:

Class Shoes:

//Declaring class shoes
public class Shoes {
   //shoe_num is an instance variable that stores the shoe number of the object
   int shoe_num;
   //cost is an array of type double that stores the total cost purchased for each shoe number
   static double [] cost= {0,0,0,0,0};
  
   //single parameter constructor that takes in shoe_num as parameter and initializes the object
   public Shoes(int shoe_num) {
       this.shoe_num = shoe_num;
   }
  
   //getter for shoe_num
   public int getShoe_num() {
       return shoe_num;
   }
  
   //setter for shoe_num
   public void setShoe_num(int shoe_num) {
       this.shoe_num = shoe_num;
   }
  
   //getter for array cost[]
   public static double[] getCost() {
       return cost;
   }
  
   //setter for array cost[]
   public static void setCost(double[] cost) {
       Shoes.cost = cost;
   }
  
   //method to update the cost of each shoe number purchased as per the quantity.
   void updateTotalSales(int qty)
   {
       //switch case for shoe_num of the instance
       switch(this.shoe_num)
       {
               //if shoe_num ==1 then cost[0] is updated
       case 1: cost[0]=cost[0]+(15.50*qty);
               break;
               //if shoe_num ==2 then cost[1] is updated
       case 2: cost[1]=cost[1]+(27.30*qty);
               break;
               //if shoe_num ==3 then cost[2] is updated
       case 3: cost[2]=cost[2]+(34.50*qty);
               break;
               //if shoe_num ==4 then cost[3] is updated
       case 4: cost[3]=cost[3]+(42.11*qty);
               break;
               //if shoe_num ==5 then cost[4] is updated
       case 5: cost[4]=cost[4]+(54.25*qty);
               break;
       }  
      
   }
  
}

Class Result:

import java.util.Scanner;
//class that contains main
public class Result {

//main method
   public static void main(String[] args) {
       // TODO Auto-generated method stub
       //declaring new scanner for input
       Scanner sc=new Scanner(System.in);
       //declaring integers shoe_num and qty to store inputs from user
       int shoe_num,qty;
      //loop is always executed
       while(true)
       {
           //prompting user to enter shoe number
           System.out.print("Shoe number: ");
           //storing it in shoe_num
           shoe_num=sc.nextInt();
           //if shoe_num==0 then we break out of the loop. This is the sentinel
           if (shoe_num==0)
               break;
           //prompting user to enter quantity sold
           System.out.print("Quantity sold: ");
           //storing it in qty
           qty=sc.nextInt();
           //initializing object s for class Shoes
           Shoes s=new Shoes(shoe_num);
           //calling updateTotalSales() method
           s.updateTotalSales(qty);
       }
       //initializing new object as the previous one was a local one
       Shoes s=new Shoes(shoe_num);
       System.out.println("Total sales");
       //declaring and initializing arr to store the cost array from class Shoes.
       double [] arr=s.getCost();
       //Printing elements of array arr
       for(int i=0;i<5;i++)
       {
           System.out.println("Shoe "+(i+1)+":$"+arr[i]);
       }

   }

}

Executable code snippets:

Class Shoes:

Class Result:

Output: