Question

Create an Interface DiscountPolicy. It should have a single abstract method computeDiscount that will return the discount for the purchase of a given number of a single item. The method has two parameters, count (int type) and itemCost (double type). Create a class BulkDiscount that implements Interface DiscountPolicy. The BulkDiscount class has two proprieties: theMinimum (int type), and percent (double type). It should have a constructor that sets the parameters, minimum and percent to a given values. It should define the method computeDiscount so that if the quantity (count) purchased of an item is more than minimum, the discount is calculated as count*itemCost*percentOff/100.0, otherwise, discount will be equal=0.0; Write a test program that tests your method. Create at least three objects of BulkDiscount class and print out their discount values. (JAVA)

Answer 1

DiscountPolicy.java

//Interface DiscountPolicy with abstract method computeDiscount
public interface DiscountPolicy {
   public double computeDiscount(int count, double itemCost);
}

BulkDiscount.java

public class BulkDiscount implements DiscountPolicy{
   //member variables
   private int theMinimum;
   private double percent;
  
   //constructor that sets the member variables
   public BulkDiscount(int minimum, double discountPercent)
   {
       theMinimum = minimum;
       percent = discountPercent;
   }
  
   //method that computes and returns the discount amount for a bulk purchase of an item
   public double computeDiscount(int count, double itemCost)
   {
       //declare and set discount amount to 0.0
       double discountAmt = 0.0;
       //if count is greater than minimum
       if(count > theMinimum)
           //compute discount amount
           discountAmt = count * itemCost * percent / 100.00;
       //return discount amount
       return discountAmt;
   }
}

TestBulkDiscount.java

public class TestBulkDiscount {

   public static void main(String[] args) {
       //create three objects of BulkDiscount class with different minimum and discount percent values
       BulkDiscount bulkObj1 = new BulkDiscount(10, 5);
       BulkDiscount bulkObj2 = new BulkDiscount(20, 5.5);
       BulkDiscount bulkObj3 = new BulkDiscount(5, 4.2);
      
       //compute and display discount amount of object 1
       double discountAmount = bulkObj1.computeDiscount(15, 59.95);
       System.out.printf("Discount Amount for bulkObj1: $%.2f",discountAmount);
      
       //compute and display discount amount of object 2
       discountAmount = bulkObj2.computeDiscount(10, 44.45);
       System.out.printf("\n\nDiscount Amount for bulkObj2: $%.2f",discountAmount);
          
       //compute and display discount amount of object 3
       discountAmount = bulkObj3.computeDiscount(20, 75.25);
       System.out.printf("\n\nDiscount Amount for bulkObj3: $%.2f",discountAmount);

   }

}

Output

Code screenshot: