Code for the ATM System

We've covered different aspects of the ATM and observed the attributes attached to the problem using various UML diagrams. Let's now explore the more practical side of things where we will work on implementing the ATM using multiple languages. This is usually the last step in an object-oriented design interview process.

We have chosen the following languages to write the skeleton code of the different classes present in the ATM system:

  • Java

  • C#

  • Python

  • C++

  • JavaScript

ATM classes

In this section, we will provide the skeleton code of the classes designed in the class diagram lesson.

Note: For simplicity, we are not defining getter and setter functions. The reader can assume that all class attributes are private and accessed through their respective public getter methods and modified only through their public method functions.

Enumerations

The following code provides the definition of the enumeration used in the ATM system.

ATMStatus: This enumeration keeps track of the following states of an ATM:

  • Idle

  • Card inserted by the user

  • Option selected

  • Cash withdrawal

  • Money transfer

  • Display the account balance

Note: JavaScript does not support enumerations, so we will be using the Object.freeze() method as an alternative that freezes an object and prevents further modifications.

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