└── OnlineBankingSystem.java


/OnlineBankingSystem.java:
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  1 | import java.util.HashMap;
  2 | import java.util.Scanner;
  3 | 
  4 | class Account {
  5 |     private String name;
  6 |     private double balance;
  7 | 
  8 |     public Account(String name) {
  9 |         this.name = name;
 10 |         this.balance = 0.0;
 11 |     }
 12 | 
 13 |     public void deposit(double amount) {
 14 |         balance += amount;
 15 |         System.out.println(amount + " deposited successfully.");
 16 |     }
 17 | 
 18 |     public void withdraw(double amount) {
 19 |         if (balance >= amount) {
 20 |             balance -= amount;
 21 |             System.out.println(amount + " withdrawn successfully.");
 22 |         } else {
 23 |             System.out.println("Insufficient balance.");
 24 |         }
 25 |     }
 26 | 
 27 |     public double getBalance() {
 28 |         return balance;
 29 |     }
 30 | }
 31 | 
 32 | public class OnlineBankingSystem {
 33 |     private static HashMap<String, Account> accounts = new HashMap<>();
 34 | 
 35 |     public static void main(String[] args) {
 36 |         Scanner scanner = new Scanner(System.in);
 37 |         boolean exit = false;
 38 | 
 39 |         while (!exit) {
 40 |             System.out.println("Welcome to Online Banking System");
 41 |             System.out.println("1. Create Account");
 42 |             System.out.println("2. Deposit");
 43 |             System.out.println("3. Withdraw");
 44 |             System.out.println("4. Check Balance");
 45 |             System.out.println("5. Exit");
 46 |             System.out.print("Enter your choice: ");
 47 |             int choice = scanner.nextInt();
 48 | 
 49 |             switch (choice) {
 50 |                 case 1:
 51 |                     System.out.print("Enter your name: ");
 52 |                     String name = scanner.next();
 53 |                     createAccount(name);
 54 |                     break;
 55 |                 case 2:
 56 |                     System.out.print("Enter your name: ");
 57 |                     String depositor = scanner.next();
 58 |                     System.out.print("Enter amount to deposit: ");
 59 |                     double depositAmount = scanner.nextDouble();
 60 |                     deposit(depositor, depositAmount);
 61 |                     break;
 62 |                 case 3:
 63 |                     System.out.print("Enter your name: ");
 64 |                     String withdrawer = scanner.next();
 65 |                     System.out.print("Enter amount to withdraw: ");
 66 |                     double withdrawAmount = scanner.nextDouble();
 67 |                     withdraw(withdrawer, withdrawAmount);
 68 |                     break;
 69 |                 case 4:
 70 |                     System.out.print("Enter your name: ");
 71 |                     String balanceChecker = scanner.next();
 72 |                     checkBalance(balanceChecker);
 73 |                     break;
 74 |                 case 5:
 75 |                     exit = true;
 76 |                     System.out.println("Thank you for using Online Banking System.");
 77 |                     break;
 78 |                 default:
 79 |                     System.out.println("Invalid choice. Please try again.");
 80 |             }
 81 |         }
 82 |         scanner.close();
 83 |     }
 84 | 
 85 |     private static void createAccount(String name) {
 86 |         if (!accounts.containsKey(name)) {
 87 |             Account account = new Account(name);
 88 |             accounts.put(name, account);
 89 |             System.out.println("Account created successfully.");
 90 |         } else {
 91 |             System.out.println("Account already exists.");
 92 |         }
 93 |     }
 94 | 
 95 |     private static void deposit(String name, double amount) {
 96 |         Account account = accounts.get(name);
 97 |         if (account != null) {
 98 |             account.deposit(amount);
 99 |         } else {
100 |             System.out.println("Account not found.");
101 |         }
102 |     }
103 | 
104 |     private static void withdraw(String name, double amount) {
105 |         Account account = accounts.get(name);
106 |         if (account != null) {
107 |             account.withdraw(amount);
108 |         } else {
109 |             System.out.println("Account not found.");
110 |         }
111 |     }
112 | 
113 |     private static void checkBalance(String name) {
114 |         Account account = accounts.get(name);
115 |         if (account != null) {
116 |             System.out.println("Balance: " + account.getBalance());
117 |         } else {
118 |             System.out.println("Account not found.");
119 |         }
120 |     }
121 | }


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