如何在一个循环中遍历多个不同类型的数组？

Question

import java.util.ArrayList;
import java.util.Scanner;

public class P8 {
    public static void main(String[] args) {
        double runningTotal = 0.00;
        double subTotal = 0.00;

        int d = 0;
        int d1 = 1;
        ArrayList<String> menuItems = new ArrayList<String>();
        ArrayList<Double> menuCost = new ArrayList<Double>();
        ArrayList<Integer> menuQuantity = new ArrayList<Integer>();
        int counter = 0;
        String[] options = {
            "Y", "y", "Yes", "yes", "YES"
        };

        boolean found = false;

        while(d < d1) {
            ++counter;
            Scanner order = new Scanner(System.in);
            System.out.print("What would you like to order? "); //item order
            String foodItem = order.nextLine();
            menuItems.add(foodItem);

            Scanner quantity = new Scanner(System.in);
            System.out.print("How many orders of that item would you like? "); //item order quantity 
            int foodQuantity = quantity.nextInt();
            menuQuantity.add(foodQuantity);

            double randNum = (double)(System.currentTimeMillis() % 11);
            menuCost.add(randNum);
            runningTotal = randNum * foodQuantity;
            subTotal += runningTotal;

            Scanner response = new Scanner(System.in);
            System.out.print("Would you like to order more items? ");
            String response1 = response.nextLine();


            for (String elements:options) {
                if (response1.equals(elements)){        
                    found = true;
                    break;
                }
            }


            if (found == true) {
                found = false;
                d = 0;  
            }


            else {
                int counter2 = 0;
                int counter3 = 1;

                while (counter2 <= counter) {

                    for (String elements:menuItems) {
                        double itemQuantity = menuQuantity.get(counter2);
                        double itemCost = menuCost.get(counter2);
                        System.out.printf("%2d%10s%5d%10.2f%10.2f\n", counter3, elements, itemQuantity, itemCost, (itemQuantity * itemCost));
                        counter2 += 1;
                        counter3 += 1;      
                    }
                }
                break;
            }

        }

    }
}

An example of what one line of this output would look like is this:

1 -- Red Wine -- -- 2 -- -- -- -- 6.25 -- -- -- -- -- 12.50

I want my code to keep iterating until the loop terminates. In Python this is extremely simple as I can simply iterate all the objects at the same time under one while-loop using the index. Unfortunately, as this is my first day actually coding in Java for one of my classes, I can't help but feel lost and think it has a completely different set of rules that I'm unable to grasp yet.

Basically, I just need to know how I can iterate over multiple array lists of different types and print them on a single line.

By the way, I am sorry but I do not know how I can format my posts correctly on this website which is why I used the horizontal lines to indicate spaces that represent the "%d and %s" of my code. I always get notifications of someone editing my post and it feels like I am getting criticized without being provided an opportunity to prevent it from happening. If someone can direct me to somewhere that shows how I can properly format my code, I would greatly appreciate it.

Answer 1

I comment out some lines to understand and solve your problem. U can see below code ;

import java.util.ArrayList;
import java.util.Scanner;
public class P8 {

    public static void main(String[] args) {
        double runningTotal = 0.00;
        double subTotal = 0.00;

        int d = 0;
        int d1 = 1;
        ArrayList<String> menuItems = new ArrayList<String>();
        ArrayList<Double> menuCost = new ArrayList<Double>();
        ArrayList<Integer> menuQuantity = new ArrayList<Integer>();
        int counter = 0;
        String[] options = {
                "Y", "y", "Yes", "yes", "YES"
        };

        boolean found = false;

        while (d < d1) {
            ++counter;
            Scanner order = new Scanner(System.in);
            System.out.print("What would you like to order? "); //item order
            String foodItem = order.nextLine();
            menuItems.add(foodItem);

            Scanner quantity = new Scanner(System.in);
            System.out.print("How many orders of that item would you like? "); //item order quantity
            int foodQuantity = quantity.nextInt();
            menuQuantity.add(foodQuantity);

            double randNum = (double) (System.currentTimeMillis() % 11);
            menuCost.add(randNum);
            runningTotal = randNum * foodQuantity;
            subTotal += runningTotal;

            Scanner response = new Scanner(System.in);
            System.out.print("Would you like to order more items? ");
            String response1 = response.nextLine();


            for (String elements : options) {
                if (response1.equals(elements)) {
                    found = true;
                    break;
                }
            }


            if (found == false) {
                found = false;
                d = 0;
            } else {
                int counter2 = 0;
                int counter3 = 1;

                //i changed this with counter2+1 , because your logic as arraylist and starts from zero. you will get outofbound exception
                while (counter2 + 1 <= counter) {

                    for (String elements : menuItems) {
                        //do it itemquantity as integer , if u want double quantity , change.
                        int itemQuantity = menuQuantity.get(counter2);
                        double itemCost = menuCost.get(counter2);
                        //and here format is wrong in itemQuantity, if your itemQuantity param  is double write %2f , if integer write %5d
                        System.out.printf("%2d %10s %5d %10.2f %10.2f\n", counter3, elements, itemQuantity, itemCost, (itemQuantity * itemCost));
                        counter2 += 1;
                        counter3 += 1;
                    }
                }
                break;
            }

        }

    }

}

This is the change I made

if (found) {
    found = false;
    d = 0;
} else {
    int counter2 = 0;
    int counter3 = 1;
    while (counter2 < counter) {
        String menuItem = menuItems.get(counter2);
        int itemQuantity = menuQuantity.get(counter2);
        double itemCost = menuCost.get(counter2);
        System.out.printf("%2d%10s%5d%10.2f%10.2f\n", counter3, menuItem, itemQuantity, itemCost, (itemQuantity * itemCost));
        counter2 += 1;
        counter3 += 1;
        if (counter2 == counter) {
            System.out.printf("%2d%10s%12s%13.2f\n", counter3, "Subtotal:", ".....", subTotal);
            double i = subTotal * 0.08625;
            System.out.printf("%2d%10s%12s%13.2f\n", counter3 + 1, "Tax:", ".....", i);
            System.out.printf("%2d%10s%12s%13.2f\n", counter3 + 2, "Total:", ".....", (subTotal + i));
            break;
        }
    }
    break;
}