Main.java

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        Bank bank = new Bank();

        while (true) {
            System.out.println("\n1. Create Account");
            System.out.println("2. Deposit");
            System.out.println("3. Withdraw");
            System.out.println("4. Check Balance");
            System.out.println("5. Exit");
            System.out.print("Choose an option: ");
            int choice = scanner.nextInt();
            scanner.nextLine(); // Consume the newline character

            switch (choice) {
                case 1:
                    System.out.print("Enter account number: ");
                    String accountNumber = scanner.nextLine();
                    bank.createAccount(accountNumber);
                    break;
                case 2:
                    System.out.print("Enter account number: ");
                    accountNumber = scanner.nextLine();
                    BankAccount depositAccount = bank.getAccount(accountNumber);
                    if (depositAccount != null) {
                        System.out.print("Enter amount to deposit: ");
                        double depositAmount = scanner.nextDouble();
                        depositAccount.deposit(depositAmount);
                    } else {
                        System.out.println("Account not found.");
                    }
                    break;
                case 3:
                    System.out.print("Enter account number: ");
                    accountNumber = scanner.nextLine();
                    BankAccount withdrawAccount = bank.getAccount(accountNumber);
                    if (withdrawAccount != null) {
                        System.out.print("Enter amount to withdraw: ");
                        double withdrawAmount = scanner.nextDouble();
                        withdrawAccount.withdraw(withdrawAmount);
                    } else {
                        System.out.println("Account not found.");
                    }
                    break;
                case 4:
                    System.out.print("Enter account number: ");
                    accountNumber = scanner.nextLine();
                    BankAccount balanceAccount = bank.getAccount(accountNumber);
                    if (balanceAccount != null) {
                        System.out.println("Current Balance: $" + balanceAccount.getBalance());
                    } else {
                        System.out.println("Account not found.");
                    }
                    break;
                case 5:
                    System.out.println("Exiting...");
                    scanner.close();
                    return;
                default:
                    System.out.println("Invalid choice. Please try again.");
            }
        }
    }
}