Assignment6: Object-Oriented Banking

Assignment created by Daniel George

Hello, everybody! For Assignment6, we are going to design a banking system using object-oriented programming and Python.

Project Requirements

Our banking system will consist of at least the following entities:

• an account, of which there are two kinds: checking and savings
• a bank customer
• at least two other classes you can think of which might be related to a banking system. Ideas could be:
  • different kinds of banks, like a consumer bank (Bank of America, Chase, etc.), investment bank, credit union, etc.
  • an ATM
  • transactions

Make sure that you have included these two methods in some form in your system:

• deposit()
• withdrawal()

You may need or may implement other methods; that's up to you! Make sure, though, that withdrawals may not exceed the available balance for at least a basic checking account in your banking system (or else, we could witness the decline of the money system as a whole).

Code

We expect that you will turn in one file: a Bank.py file which contains your object-oriented code.

Getting Started

This assignment will give you an opportunity to think creatively and also implement concrete code. It will probably be helpful to refer back to lecture 14, in which we explored object-oriented programming. Think about what entities your system will include, as well as which attributes each class will need. In particular, think about the relationships between entities: what pairs of entities demonstrate "has-a" relationships and what entities demonstrate "is-a" relationships (see the lecture notes for how to code these up!). Remember: one of the goals of CS253, and of great software engineering, is having a vision for the "big picture" (i.e., this kind of design) as well as the granular details.

In Python, setting up a class looks like this:

class Bank:
    def __init__(self, attribute, num=100):
        self.attribute = attribute
        self.number = num
    def bank_method(self, num):
        result = self.number + num
        return result
    # other methods and class attributes

A couple of notes about the above code:

• the __init__(self) method is called an initializer. If you have worked with Java or C++ before, you might be familiar with the concept of a constructor instead; for our purposes these are the same thing (but just know that technically they are different things). A Python initializer establishes the state (meaning, all of the variables and methods as well as their values) when a Python object is instantiated (which is a fancy word to mean, "made an instance of").
• self refers to the object itself, and needs to be passed as an argument to every method belonging to the class.
• you can include named arguments like num=num or plain arguments in the function definitions, same as writing Python functions, which you are already used to.

In this assignment, you will definitely need more than just one class. It's not required that you actually run your code, but your submission should be logically coherent. In the event that you were to run your code, in Python, that works like this:

# to instantiate a class, assign an instance of that class to a variable, which looks like this syntactically
b = Bank("Daniel's Bank") # based on the code above, I pass in the string "Daniel's Bank" as the "attribute" arg

# I can now call methods belonging to the class, like this
result = b.bank_method(100)

# this will show 200
print(result)

Due Date and Final Notes

Assignment 6 will be due on December 8, 2023 at 11:59pm CST. Above all...have some fun with this and your new skills with object-oriented programming!