As usual: TDD please
A Bank Account has a balance, an interest rate and a monthly fee.
For example if a person has an interest rate of 12% (which is totally unrealistic but make the numbers easier) and they have R1000 in their bank account then they will receive (R1000 x 12% / 12) after one month of saving. That means they earned R10 in interest. Now if their monthly fee on that account is R50 then their final balance after 1 month is R1000+R10-R50 = R960.
BankAccount. it should be constructed with the necessary parameters described above.finishMonth(js) or finish_month(python). This function should update the balance accordinglybalance of a bank account can also change if a deposit or withdrawal is made. Create a function called deposit and another one called withdrawCreate a class called Bank. A Bank contains many bank accounts. A bank associates each bank account with a 10 digit number known as a bank account number. In OOP, this is called encapsulation.
Create the following functions on your Bank class:
JavaScript:
withdraw(bankAccountNumber,amount)deposit(bankAccountNumber,amount)transfer(fromBankAccountNumber,toBankAccountNumber, amount)Python:
withdraw(bank_account_number,amount)deposit(bank_account_number,amount)transfer(from_bank_account_number,to_bank_account_number, amount)This part is a little bit advanced. Stop and think before you write any code. Have a plan. Maybe even draw a picture of your plan
Create a class called Customer. A customer can be associated with multiple bank accounts. Each customer also has a secret password. The customer should be able to update their password through use of a setPassword(js) or set_password(python) function.
Whenever money is taken out of a bank account then the relevent customer’s secret password must be checked. You don’t need a special password when depositing money.
Update your Bank functions to be like this:
JavaScript:
withdraw(bankAccountNumber,amount,secretPassword)deposit(bankAccountNumber,amount)transfer(fromBankAccountNumber,toBankAccountNumber,amount,secretPassword)Python:
withdraw(bank_account_number,amount,secret_password)deposit(bank_account_number,amount)transfer(from_bank_account_number,to_bank_account_number,amount,secret_password)If a password is required and the wrong one is provided then raise an error that says wrong password.
For now just keep it simple. Just store Customer’s passwords in plain text in a variable on the appropriate object. Of course in real life, password managment and storage is kinda tricky. Here’s a nice article from Mozilla that will give you some background on how to do it the right way.