Design and Implementation of a Banking System (1) ANISH assignment

NIT5150 – Advanced Object- Oriented Programming STUDENT NAME: ANISH SHARMA NATH STUDENT ID: s8106903 0

Introduction In the world's financial system, the banking industry is essential. A strong and adaptable banking system is needed to effectively manage numerous account types, including current accounts, deposit accounts, limited accounts, and overdraft accounts. The design and implementation of a banking system in Python that takes into consideration the various types of accounts and their functionality are shown in this study. Problem Analysis and Design Considerations This project's goal was to create and put into operation a banking system that could manage various account types, including current accounts, deposit accounts, restricted accounts, and accounts with overdraft facilities. The following were the main design considerations:  Establishing a class hierarchy to represent different sorts of accounts.  Using polymorphism to enable consistent management of various account types.  Offering menu-driven user interface for user interaction.  A table-format display of account information to enhance user experience.  Preserving account data to a file in order to ensure data permanence. 1

class CurrentAccount ( Account ): def __init__ ( self , name , account_number , balance ): super (). __init__ ( name , account_number , balance ) self . cheque_book = self . generate_cheque_book () def generate_cheque_book ( self ): # Generate a random chequebook of 10 random characters return '' . join ( random . choices ( string . ascii_uppercase + string . digits , k = 10 ))  class DepositAccount(Account): class DepositAccount ( Account ): def __init__ ( self , name , account_number , balance , withdrawal_limit , interest_rate ): super (). __init__ ( name , account_number , balance ) self . withdrawal_limit = withdrawal_limit self . interest_rate = interest_rate  class RestrictedAccount(CurrentAccount): class RestrictedAccount ( CurrentAccount ): def __init__ ( self , name , account_number , balance , max_withdrawal_limit ): super (). __init__ ( name , account_number , balance ) self . max_withdrawal_limit = max_withdrawal_limit def withdraw ( self , amount ): if amount <= self . balance and amount <= self . max_withdrawal_limit : self . balance -= amount return f "Withdrawal successful. Remaining balance: { self . balance } " else : return "Withdrawal limit exceeded or insufficient funds."  class OverdraftAccount(CurrentAccount): class OverdraftAccount ( CurrentAccount ): def __init__ ( self , name , account_number , balance , overdraft_limit ): super (). __init__ ( name , account_number , balance ) self . overdraft_limit = overdraft_limit def withdraw ( self , amount ): if amount <= self . balance + self . overdraft_limit : self . balance -= amount 3

return f "Withdrawal successful. Remaining balance: { self . balance } " else : return "Withdrawal amount exceeds overdraft limit." Polymorphism in Action Polymorphism is one of the important design ideas we used in our approach. We can treat objects with various account types consistently thanks to polymorphism. Any account type is accepted by the 'withdraw_from_account' method in the 'Bank' class, which then runs the proper 'withdraw' function based on the account type. def withdraw_from_account ( self , account_number , amount ): account = self . find_account ( account_number ) if account : return account . withdraw ( amount ) else : return "Account not found." def deposit_to_account ( self , account_number , amount ): account = self . find_account ( account_number ) if account : return account . deposit ( amount ) else : return "Account not found." …. Difficulties Polymorphism Implementation It was difficult to implement polymorphism to handle various account types. It needed creating a flexible framework so that the Bank class could easily interact with any sort of account. To get around this problem, careful design and attention to object-oriented concepts were required. User Interface 4

Show Account Information We checked to make sure the table-based display of account information functioned as planned. This required making sure the table structure was aesthetically pleasing and that the account types, account numbers, names, and balances were all accurate. 6

Data Retention By utilizing the pickle module to save account data to a file and confirming that accounts could be loaded from the file upon program restart, data durability was confirmed. Account data was appropriately serialized and deserialized, according to this verification. 7

def deposit(self, amount): self.balance += amount return f"Deposit successful. New balance: {self.balance}" class CurrentAccount(Account): def __init__(self, name, account_number, balance): super().__init__(name, account_number, balance) self.cheque_book = self.generate_cheque_book() def generate_cheque_book(self): # Generate a random checkbook of 10 random characters return ''.join(random.choices(string.ascii_uppercase + string.digits, k=10)) class DepositAccount(Account): def __init__(self, name, account_number, balance, withdrawal_limit, interest_rate): super().__init__(name, account_number, balance) self.withdrawal_limit = withdrawal_limit self.interest_rate = interest_rate def withdraw(self, amount): if amount <= self.balance and amount <= self.withdrawal_limit: self.balance -= amount return f"Withdrawal successful. Remaining balance: {self.balance}" else: return "Withdrawal limit exceeded or insufficient funds." class RestrictedAccount(CurrentAccount): def __init__(self, name, account_number, balance, max_withdrawal_limit): super().__init__(name, account_number, balance) self.max_withdrawal_limit = max_withdrawal_limit 9

def withdraw(self, amount): if amount <= self.balance and amount <= self.max_withdrawal_limit: self.balance -= amount return f"Withdrawal successful. Remaining balance: {self.balance}" else: return "Withdrawal limit exceeded or insufficient funds." class OverdraftAccount(CurrentAccount): def __init__(self, name, account_number, balance, overdraft_limit): super().__init__(name, account_number, balance) self.overdraft_limit = overdraft_limit def withdraw(self, amount): if amount <= self.balance + self.overdraft_limit: self.balance -= amount return f"Withdrawal successful. Remaining balance: {self.balance}" else: return "Withdrawal amount exceeds overdraft limit." class Bank: def __init__(self): self.accounts = [] def add_account(self, account): self.accounts.append(account) def find_account(self, account_number): for account in self.accounts: if account.account_number == account_number: return account return None 10

table.add_row([type(account).__name__, account.account_number, account.name, account.balance]) return table def display_account_by_name(accounts, name): found_accounts = [account for account in accounts if account.name == name] if found_accounts: table = PrettyTable() table.field_names = ["Account Type", "Account Number", "Name", "Balance"] for account in found_accounts: table.add_row([type(account).__name__, account.account_number, account.name, account.balance]) return table else: return "No accounts found with that name." if __name__ == "__main__": bank = Bank() filename = "accounts.pkl" # File to save account information # Load accounts from file if available bank.accounts = load_accounts_from_file(filename) while True: print("\nBanking System Menu:") print("1. Add Account") print("2. Withdraw from Account") print("3. Deposit to Account") 12

print("4. Display Accounts") print("5. Display Account by Name") print("6. Save Accounts to File") print("7. Exit") choice = input("Enter your choice: ") if choice == '1': account_type = input("Enter account type (Current/Deposit/Restricted/Overdraft): ") name = input("Enter account holder name: ") account_number = input("Enter account number: ") balance = float(input("Enter initial balance: ")) if account_type == 'Current': account = CurrentAccount(name, account_number, balance) elif account_type == 'Deposit': withdrawal_limit = float(input("Enter withdrawal limit: ")) interest_rate = float(input("Enter interest rate: ")) account = DepositAccount(name, account_number, balance, withdrawal_limit, interest_rate) elif account_type == 'Restricted': max_withdrawal_limit = float(input("Enter max withdrawal limit: ")) account = RestrictedAccount(name, account_number, balance, max_withdrawal_limit) elif account_type == 'Overdraft': overdraft_limit = float(input("Enter overdraft limit: ")) account = OverdraftAccount(name, account_number, balance, overdraft_limit) else: print("Invalid account type.") continue 13

else: print("Invalid choice. Please choose a valid option.") 15