Question

All code will be in Java, and there will be TWO source code.

I. Write the class  MailOrder to provide the following functions:

At this point of the class, since we have not gone through object-oriented programming and method calling in detail yet, the basic requirement in this homework is process-oriented programming with all the code inside method processOrderof this class. Inside method processOrder, we still follow the principles of structured programming.  

Set up one one-dimensional array for each field: product number (integer), unit price (double), and current inventory level (integer) in main memory to hold the above product information. There should be five rows (0 to 4) in each array, one for each item. For example, row 0 of the array for the product number is to hold the product number of product 10012. Row 0 of the array for the unit price is to hold the unit price of product 10012.  Row 0 of the array for the current inventory level is to hold the current inventory level of product 10012, etc.

The system should accept one incoming sales order.  In this sales order, the user can buy more than one item. For each item, the system accepts the product number and the quantity to be purchased.  The system retrieves the correct unit price and current inventory level for that particular item.  The system only sells up to the current inventory available.  If the system can sell x pieces of this item in this order, the system calculates and displays the total amount for this item and also decreases the item inventory level by x immediately.  When the user has finished keying in all the items of an order, the system displays the order total amount.   Then the system should end the execution of the system.

Detailed description of how the system should work is as follows:

When execution of the system is started:

• Correctly define and initialize all variables

• Display the following main question:

Please enter the next product number to buy or -99 = end:<user enters a product number or -99>

You can assume that the user will enter an integer value.  

• While the just-received product number is not -99

{

• Search for the corresponding product number in the product number array.

• If this product is found:

• If the current inventory level is > 0,

1. display “Unit Price: <the unit price of this item>“ and “Current Quantity Available: <the current inventory level of this item>” and

(b)ask for the quantity ordered, “Enter quantity ordered:”<user enters the quantity ordered>.

You can assume that the user will key in a positive integer value.

            

If the quantity available is smaller than the quantity ordered, sell only the quantity available. Otherwise, sell the ordered quantity.

Display “Quantity Sold: <the quantity that can be sold>”

Calculate the amount for this item as Unit Price * Quantity Sold.

Display the amount for this item: “Item Amount: $ <the amount

            calculated>”

                                                            Add this amount to the current order total amount.

                                                            Since this item has been sold, update the current inventory level of this

                                                                        item.

            Else this means inventory level is 0: display “This item is out of stock. Please pick another one.”

                              Else this product is not found, display an error message “Invalid product number.”

• Display the following main questionagain before the end of the while loop

Please enter the next product number to buy or -99 = end):<user enters a product number or -99>

You can assume that the user will enter an integer value.

} // end of the while loop

• When control comes to here, this means the user has entered a -99 for the next product number, the system displays the total amount of this order. For example:

Order Total Amount:         $  72.83

• Then, the system displays the message “Bye” and execution ends.

II. Write the class MailOrderTest to provide the following functions:

In method mainof this application, instantiate an object of MailOrderand call the method processOrderof this MailOrderobject to start order processing.

DO NOT USE Until loop (the “do-while” loop in Java)

Answer 1

class MailOrder

{

public processOrder()

{

int[] product_number={10011, 10012, 10013, 10014, 10015};

float[] unit_price={10.5, 11.2, 20.4, 30, 25};

int[] inventory_level={10, 20, 30, 40,50};

double total_amt=0;

double final_amt=0

Scanner myObj = new Scanner(System.in);  // Create a Scanner object
    System.out.println("Please enter the next product number to buy or -99 = end");

    int no = myObj.nextInt();  // Read user input

while(no !=-99)

{

for(int i=0;i<product_number.length;i++)

{    

            if(product_number[i] == no)

{    

if(inventory_level>0)

{

  System.out.println("current inventory level is"+inventory_level[i]);

   System.out.println("unit price is"+unit_pricel[i]);

  System.out.println("Enter quatity of that product");

  int quantity = myObj.nextInt();

if(quantity<= inventory_level[i] )

{

  System.out.println("product sold as per your requirement"+ quantity);

total_amt=quantity*unit_price;

  System.out.println("Total amount will be"+ total_amt);

  System.out.println("Remaining quantity is"+ inventory_level[i]-quantity);

final_amt=final_amt+total_amt;

System.out.println("Final amount will be"+ final_amt);

}

else

{

System.out.println("we can sell only what we have "+ inventory_level[i]);

total_amt=inventory_level[i]*unit_price;

  System.out.println("Total amount will be"+ total_amt);

System.out.println("now product is out of stock please pick another one");

final_amt=final_amt+total_amt;

System.out.println("Final amount will be"+ final_amt);

}

}

}

else{System.out.println("This product is not available ");}

System.out.println("Please enter the next product number to buy or -99 = end");

}//end of while loop

   System.out.println("Total amout of all product is"+final_amt);

    System.out.println("Bye");

  

            }    

}

public class MailOrderTest

{

public static void main(String args[])

{

  MailOrder m = new MailOrder();

m.processOrder();

}

}