Java Bank System

A fully functional, console-based banking system built in Java.

This project was initially created as a school project, but I decided to step it up and challenge myself by learning about databases. To practice, I tried to mock a simple database for storing user and transaction data.

Features

• User Registration & Login: Secure registration with unique username and 4-digit PIN.
• Account Management: View account details, balance, and masked PIN.
• Deposits & Withdrawals: Deposit or withdraw funds with transaction tracking.
• Fund Transfers: Transfer money between accounts using unique account numbers.
• Transaction History: View a detailed history of all account transactions.
• PIN Change: Securely update your account PIN.
• Persistent Storage: All user data and transactions are saved in users.json.

Running the Application

• Java 8 or higher installed on your system.

1. Clone or Download the Repository
2. Compile the Source Files:

   javac src/*.java

3. Run the Application:

   java -cp src Runner

File Structure

• src/Account.java - Account model
• src/Transaction.java - Transaction model
• src/UserManager.java - Handles user data and persistence
• src/Runner.java - Main application logic and user interface
• users.json - Stores all user and transaction data

Usage

• Register: Create a new account with a unique username and PIN.
• Login: Access your account using your credentials.
• Main Menu: Choose actions like deposit, withdraw, transfer, view history, or change PIN.
• Logout: Securely log out when finished.

License

• MIT

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Thanks for checking out my project! If you like it, please give it a ⭐ on GitHub.