Thread: Storefront Exercise Troubles

import java.text.NumberFormat;
import java.util.Locale;
import java.util.Scanner; //Scanner Class Available

public class Pies {

/**
* @param args
*/
public static void main(String[] args) {

Scanner inScan = new Scanner(System.in);
NumberFormat formatter = NumberFormat.getCurrencyInstance(Locale.US);
//
while (true)
{
System.out.println("Is there another customer waiting in line?");
String newCustomer = inScan.nextLine();
while (newCustomer.equalsIgnoreCase("Y") || newCustomer.equalsIgnoreCase("Yes"))
{
System.out.println("Are you a Pi Card Member?");
String cardHolder = inScan.nextLine();
while (cardHolder.equalsIgnoreCase("Y") || cardHolder.equalsIgnoreCase("Yes"))
{
System.out.println("Here's a list of products for sale:");
System.out.println("(a) Cheese Pizza $10.00");
System.out.println("(b) Pepperoni Pizza $10.00");
System.out.println("(c) Cherry Pies $ 8.00");
System.out.println("(d) Cherry Pie Slices $ 1.75");
System.out.println("(e) Pi Charms (14k Gold) $45.00");
System.out.println("(f) Checkout");
System.out.println(System.getProperty("line.separa tor"));
System.out.println("Which item would you like to purchase? (a,b,c,d, or e)");
String addCart = inScan.nextLine();
if (addCart.equalsIgnoreCase("A"))
{
System.out.println("How many Cheese Pizzas would you like to purchase?");
double numberCheesePizzas = inScan.nextDouble();
double cheesePizzaCost = 10.00;
double cheeseTotal = (cheesePizzaCost * numberCheesePizzas);
System.out.println("You have a total of " + numberCheesePizzas + " Cheese Pizzas in your cart for a total of $" + cheeseTotal + ".");
System.out.println(System.getProperty("line.separa tor"));
}
if (addCart.equalsIgnoreCase("B"))
{
//and so on I didn't want to copy the entire code when i really just need help with making the individual loops work--
}

}

}

}

}

}


The goal of the entire exercise is to allow multiple items to be put into a "basket", purchased, with sales tax, etc. None of that is important right now but can someone help me understand why the output for this using (a) and any number causes the loop to output the list of items and prices twice? ITS KILLING ME INSIDE TRYING TO FIGURE THIS OUT!

Sample Output:

Is there another customer waiting in line?
Y
Are you a Pi Card Member?
Y
Here's a list of products for sale:
(a) Cheese Pizza $10.00
(b) Pepperoni Pizza $10.00
(c) Cherry Pies $ 8.00
(d) Cherry Pie Slices $ 1.75
(e) Pi Charms (14k Gold) $45.00
(f) Checkout


Which item would you like to purchase? (a,b,c,d, or e)
A
How many Cheese Pizzas would you like to purchase?
23
You have a total of 23.0 Cheese Pizzas in your cart for a total of $230.0.


Here's a list of products for sale:
(a) Cheese Pizza $10.00
(b) Pepperoni Pizza $10.00
(c) Cherry Pies $ 8.00
(d) Cherry Pie Slices $ 1.75
(e) Pi Charms (14k Gold) $45.00
(f) Checkout


Which item would you like to purchase? (a,b,c,d, or e)
Here's a list of products for sale:
(a) Cheese Pizza $10.00
(b) Pepperoni Pizza $10.00
(c) Cherry Pies $ 8.00
(d) Cherry Pie Slices $ 1.75
(e) Pi Charms (14k Gold) $45.00
(f) Checkout


Which item would you like to purchase? (a,b,c,d, or e)

Sorry about the poorly posted code. In regards to your advice of putting it down on paper i already have as well as just made small changes to the code to see what's wrong but to no avail.

import java.text.NumberFormat;
import java.util.Locale;
import java.util.Scanner;	//Scanner Class Available
 
public class Pies {
 
	/**
	 * @param args
	 */
	public static void main(String[] args) {
 
		Scanner inScan = new Scanner(System.in);
		NumberFormat formatter = NumberFormat.getCurrencyInstance(Locale.US);	
		//
		while (true)
			{
			System.out.println("Is there another customer waiting in line?");
			String newCustomer = inScan.nextLine();
			while (newCustomer.equalsIgnoreCase("Y") || newCustomer.equalsIgnoreCase("Yes"))
				{
					System.out.println("Are you a Pi Card Member?");
					String cardHolder = inScan.nextLine();
					while (cardHolder.equalsIgnoreCase("Y") || cardHolder.equalsIgnoreCase("Yes"))
						{
							String addCart ="x";
							System.out.println("Here's a list of products for sale:");
							System.out.println("(a) Cheese Pizza				$10.00");
							System.out.println("(b) Pepperoni Pizza				$10.00");
							System.out.println("(c) Cherry Pies					$ 8.00");
							System.out.println("(d) Cherry Pie Slices				$ 1.75");	
							System.out.println("(e) Pi Charms (14k Gold)			$45.00");
							System.out.println("(f) Checkout");
							System.out.println(System.getProperty("line.separator"));
							System.out.println("Which item would you like to purchase? (a,b,c,d, or e)");
							addCart = inScan.nextLine();
						if (addCart.equalsIgnoreCase("A"))
							{
								System.out.println("How many Cheese Pizzas would you like to purchase?");
								double numberCheesePizzas = inScan.nextDouble();
								double cheesePizzaCost = 10.00;
								double cheeseTotal = (cheesePizzaCost * numberCheesePizzas);
								System.out.println("You have a total of " + numberCheesePizzas + " Cheese Pizzas in your cart for a total of $" + cheeseTotal + ".");
								System.out.println(System.getProperty("line.separator"));
							}
						if (addCart.equalsIgnoreCase("B"))	
							{
								//and so on I didn't want to copy the entire code when i really just need help with making the individual loops work--
							}
 
						}
 
				}
 
		}
 
	}
 
}

Originally Posted by Norm

One problem is with the way the Scanner class works. When it reads a whole line into its buffer that includes the lineend character. The nextLine() method removes everything from the buffer including the lineend character. The nextDouble() method does not remove the lineend character from the buffer so that the next call to nextLine() returns nothing as it removes the lineend from the buffer.
To see this add a System.out.println("an ID "+<THESTRINGHERE> + "<");
that prints out what is called after the call to nextLine() following the call to nextDouble().

I have gone back through and attempted to see what the computer is seeing, but for the life of me I can not figure out why it System.out.println this section where it lists the items and prices twice! Does it have something to do with the System.out.println(System.getProperty("line.separa tor")) entry??

import java.text.NumberFormat;
import java.util.Locale;
import java.util.Scanner;	//Scanner Class Available
 
public class Pies {
 
	/**
	 * @param args
	 */
	public static void main(String[] args) {
 
		Scanner inScan = new Scanner(System.in);
		NumberFormat formatter = NumberFormat.getCurrencyInstance(Locale.US);	
		//
		while (true)
			{
			System.out.println("Is there another customer waiting in line?");
			String newCustomer = inScan.nextLine();
			System.out.println(newCustomer);
			while (newCustomer.equalsIgnoreCase("Y") || newCustomer.equalsIgnoreCase("Yes"))
				{
					System.out.println("Are you a Pi Card Member?");
					String cardHolder = inScan.nextLine();
					//System.out.println(cardHolder);
					while (cardHolder.equalsIgnoreCase("Y") || cardHolder.equalsIgnoreCase("Yes"))
						{
							String addCart ="";
							System.out.println("Here's a list of products for sale:");
							System.out.println("(a) Cheese Pizza				$10.00");
							System.out.println("(b) Pepperoni Pizza				$10.00");
							System.out.println("(c) Cherry Pies					$ 8.00");
							System.out.println("(d) Cherry Pie Slices				$ 1.75");	
							System.out.println("(e) Pi Charms (14k Gold)			$45.00");
							System.out.println("(f) Checkout");
							System.out.println(System.getProperty("line.separator"));
							System.out.println("Which item would you like to purchase? (a,b,c,d, or e)");
							addCart = inScan.nextLine();
							//System.out.println(addCart);
						if (addCart.equalsIgnoreCase("A"))
							{
								System.out.println("How many Cheese Pizzas would you like to purchase?");
								double numberCheesePizzas = inScan.nextDouble();
								//System.out.println(numberCheesePizzas);
								double cheesePizzaCost = 10.00;
								double cheeseTotal = (cheesePizzaCost * numberCheesePizzas);
								System.out.println("You have a total of " + numberCheesePizzas + " Cheese Pizzas in your cart for a total of $" + cheeseTotal + ".");
								System.out.println(System.getProperty("line.separator"));
							}
						if (addCart.equalsIgnoreCase("B"))	
							{
								//and so on I didn't want to copy the entire code when i really just need help with making the individual loops work--
							}
 
						}
 
				}
 
		}
 
	}
 
}

I'm not sure what else I can do because it's not that I don't understand how the while loop works, I just don't understand why the loop is activating twice without user input on what item should be purchased! Quite frustrating...