How to print full Arraylist which is stored in a HashMap - arraylist

Question

I need some assistance to get my assignment working.
Goal is to get a shopping cart which is used by different buyer and everybody can add some article to his shopping cart. My idea is to create an arraylist of all articles I put into the shopping cart and map the created arraylist with the hashmap key, string name of the buyer.
Unfortunatelly If I wanna print out the articles for each buyer, I even get all articles of all buyers. To be honest I'm quite new to this and still unsure if this is the right way to get this working. Before I tried Hasmap I wanted to have dynamic name of my arraylists, means the name of the arraylist of article should be the buyer name.
public class Main {
private static Scanner sc = new Scanner(System.in);
public static void main(String[] args) {
int amount;
String customerName = "";
System.out.println("Wieviel Benutzer möchten einkaufen?");
amount = Integer.parseInt(sc.nextLine());
for (int i = 0; i < amount; i++) {
System.out.println("Name eingeben:");
customerName = sc.nextLine();
Warenkorb.initialCreation(customerName);}}}
class Warenkorb {
private static ArrayList<Artikel> shoppingCart = new ArrayList<>();
private static HashMap<String, ArrayList<Artikel>> map = new
HashMap<String, ArrayList<Artikel>>();
private static Scanner sc = new Scanner(System.in);
public static void initialCreation(String customerName) {
String currentUser = customerName;
int amountofitem;
System.out.println("How many Arcticle do you want to create");
amountofitem = Integer.parseInt(sc.nextLine());
for (int i = 0; i < amountofitem; i++) {
String artikelName = "";
int price, qty;
System.out.println(">>>Add Article<<<");
System.out.println("Please enter article name");
artikelName = sc.nextLine().trim().toString();
System.out.println("Please enter price");
price = Integer.parseInt(sc.nextLine());
System.out.println("Please enter how many you would like to add -> quantity");
qty = Integer.parseInt(sc.nextLine());
Artikel bla = new Artikel(artikelName, qty, price);
shoppingCart.add(bla);
}
map.put(currentUser, shoppingCart);
for (Map.Entry<String, ArrayList<Artikel>> entry : map.entrySet()) {
System.out.println("Shopping Cart of " + entry.getKey());
for (Artikel item : entry.getValue()) {
System.out.println("Artikel" + " " + item.getItemName() + " " + item.getItemPrice() + "€ " + item.getItemTax() + "%.");
}
}
}
This is what I get if I try to print out each shoppingcart:
Shopping Cart of PEter
Artikel Apfel 3€ 3%.
Artikel Banana 3€ 3%.
Shopping Cart of Chris
Artikel Apfel 3€ 3%.
Artikel Banana 3€ 3%.

Answer 1

The problem is that your shoppingCart and map are defined in static context of the class. Every time you call initialCreation method it deals with the same collections. I'd suggest to make collections non-static and initialCreated method as well.

Answer 2

public class Main {
private static Scanner sc = new Scanner(System.in);
public static void main(String[] args) {
int amount;
String customerName = "";
System.out.println("Wieviel Benutzer möchten einkaufen?");
amount = Integer.parseInt(sc.nextLine());
for (int i = 0; i < amount; i++) {
System.out.println("Name eingeben:");
customerName = sc.nextLine();
new Warenkorb().initialCreation(customerName);
}
}
}
class Warenkorb {
private ArrayList<String> shoppingCart = new ArrayList<>();
private HashMap<String, ArrayList<String>> map = new HashMap<>();
private Scanner sc = new Scanner(System.in);
public void initialCreation(String customerName) {
// you code
}
}
Something like that.