ByteBank ATM System

Overview

This project is a Java-based ATM simulation that connects a graphical user interface with a backend banking logic. It allows users to create a personal account, choose from a list of different ATM locations, and perform standard banking transactions like depositing or withdrawing money. A "Saboteur" logic is included that randomly disables ATMs to simulate real-world hardware failures.

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Features

• User Initialization: On startup, the system prompts for a name, initial balance, and a 4-digit security PIN to create a BankAccount.
• ATM Selection Grid: A visual interface displays 10 different ATM locations based on real-world spots like "Mürzzuschlag" or "Leoben".
• Real-time Console: A text area in the UI logs every system action, including successful logins and error reports.
• Transaction Management: Supports withdrawing money, depositing funds, and checking the current balance.
• Saboteur System: Every access triggers a chance for a random ATM in the network to be sabotaged and set to "offline" status.

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Technical Structure

The project uses a modular approach with custom Exception classes for error handling:

• Core Logic:
  • BankAccount.java: Handles customer data, PIN storage, and balance.
  • ATM.java: Manages the link between the user account and the terminal.
  • Saboteur.java: Contains the logic for random ATM status changes.
• Custom Exceptions:
  • InvalidPinTypeException: Thrown if the PIN is not exactly 4 digits.
  • InvalidDrawAmount: Triggered when withdrawal exceeds the current balance.
  • InputTypeMissmatch: Handles invalid data types during user input.
• Interface:
  • GUI.java: The main entry point using Java Swing for the graphical interface.

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Project Background

This is a school project created to practice the fundamentals of Object-Oriented Programming (OOP) in Java. The main focus was on learning how to structure classes, handle custom exceptions, and specifically understanding the use of static members (like global transaction and account counters).

Note on Development: While the core logic and exception handling were written manually, the Graphical User Interface (GUI) was generated with the help of AI to achieve a more modern look and feel.

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Setup and Execution

1. Requirements:
   • Java Runtime Environment (JRE) 17 or higher.
2. Installation:
   • Import all .java files into your IDE.
   • Ensure all files are in the package atm_wetzlhuetter.
   • Delete module-info.java if you see "package javax.swing is not accessible" errors.
3. Running:
   • Start the application by running the main method in GUI.java.

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How to Download and Run (.exe)

If you just want to test the application without looking at the code, follow these steps:

1. Go to Releases: Navigate to the "Releases" section on the right side of this GitHub repository.
2. Download: Find the latest version and download the ByteBank_ATM.exe file from the "Assets" section.
3. Java Requirement: Make sure you have at least Java 17 installed on your Windows machine, as the executable requires a local Java Runtime Environment to start.
4. Launch: Double-click the .exe file. If Windows shows a "SmartScreen" warning (because the file is not digitally signed), click on "More info" and then "Run anyway".