Question

Please add comments to this code!

JAVA Code:

import java.text.NumberFormat;
public class Item {

   private String name;
   private double price;
   private int bulkQuantity;
   private double bulkPrice;

   /***
   *
   * @param name
   * @param price
   * @param bulkQuantity
   * @param bulkPrice
   */
   public Item(String name, double price, int bulkQuantity, double bulkPrice) {
       this.name = name;
       this.price = price;
       this.bulkQuantity = bulkQuantity;
       this.bulkPrice = bulkPrice;

   }

   public Item(String name, double price) {
       if (price < 0) {
           throw new IllegalArgumentException();
       }

       this.name = name;
       this.price = price;

   }

   /***
   *
   * @param quantity
   * @return
   */
   public double priceFor(int quantity) {
       double actual = 0;
       if (quantity < 0) {
           throw new IllegalArgumentException();
       } else {
           if (bulkQuantity!=0) {
               actual = (quantity / bulkQuantity) * bulkPrice
                       + (quantity % bulkQuantity) * price;
           } else {
               actual = quantity * price;
           }
       }

       return actual;

   }

   public boolean equals(Item ietm) {
       return this.name.equals(ietm.name);
   }

   @Override
   public String toString() {
       NumberFormat format = (NumberFormat) NumberFormat.getCurrencyInstance();

       format.setMinimumFractionDigits(2);
       format.setMaximumFractionDigits(2);
       String str = "";
       str = name + ", " + format.format(price);
       if (bulkPrice != 0) {
           str += " ( " + bulkQuantity + " for " + format.format(bulkPrice)
                   + " )";
       }
       return str;
   }
}

Thanks!!

Answer 1

import java.text.NumberFormat;
public class Item {

        // instance variale of string name
   private String name;
        // instance variale of double price
   private double price;
        // instance variale of int quantity
   private int bulkQuantity;
        // instance variale of double price
   private double bulkPrice;

   /***
   *
   *Constructor takes 4 arguments and assigns to instance variables
   * @param name
   * @param price
   * @param bulkQuantity
   * @param bulkPrice
   */
   public Item(String name, double price, int bulkQuantity, double bulkPrice) {
           // assinging to name
       this.name = name;
       //assigning to price
       this.price = price;
       //assigning to bulkQuantity 
       this.bulkQuantity = bulkQuantity;
     //assigning to bulkPrice
       this.bulkPrice = bulkPrice;

   }

   /**
    * Another constructor which takes name and price as arguments
 * @param name
 * @param price
 */
public Item(String name, double price) {
        //checking if price is negative than throwing the exception
       if (price < 0) {
           throw new IllegalArgumentException();
       }
       // if everything is good assigning the data
       this.name = name;
       this.price = price;

   }

   /***
   *
   * @param quantity
   * @return totalPrice for given quantity
   */
   public double priceFor(int quantity) {
       double actual = 0;
       //if quantity is negative than throwing exception
       if (quantity < 0) {
           throw new IllegalArgumentException();
       } else {
           if (bulkQuantity!=0) {
                   // calculating the actual price if bulkQuantity is not zero 
               actual = (quantity / bulkQuantity) * bulkPrice
                       + (quantity % bulkQuantity) * price;
           } else {
                   // calculating the actual price if bulkQuantity is  zero
               actual = quantity * price;
           }
       }

       //returning actual price
       return actual;

   }

   //checks the equality of 2 items
   public boolean equals(Item ietm) {
           //checking equality based on the name
       return this.name.equals(ietm.name);
   }

   @Override
   public String toString() {
           //creating NumberFormat to format the price to 2 fraction digits
       NumberFormat format = (NumberFormat) NumberFormat.getCurrencyInstance();
       format.setMinimumFractionDigits(2);
       //setting the fractions 2
       format.setMaximumFractionDigits(2);
       String str = "";
       //formating the price and name
       str = name + ", " + format.format(price);
       if (bulkPrice != 0) {
           str += " ( " + bulkQuantity + " for " + format.format(bulkPrice)
                   + " )";
       }
       return str;
   }
}