Applications of OOP in Real-Time Software

I am going to tell you how to use OOP concepts to build real-time software applications, particularly an Online Banking System. OOP helps in structuring the code, making it modular, and enhancing reusability and maintainability.

OOP Concepts Used

Encapsulation: Protects data by restricting direct access to it and exposing only necessary methods. Inheritance: Allows the creation of a new class based on an existing class, promoting code reusability. Polymorphism: Enables methods to do different things based on the object calling them.

Building an Online Banking System

1. User Class The User class handles user registration and login functionality.

class User {
private:
    string name;
    string userID;
    string password;

public:
    void registerUser(string userName, string userPassword) {
        name = userName;
        userID = generateUserID(); // Generate a unique user ID
        password = userPassword;
        // Logic to store user data in a database
    }

    bool login(string userPassword) {
        return password == userPassword; // Validate password
    }
};

2. Account Class The Account class manages the bank account operations such as deposits and withdrawals.

class Account {
private:
    string accountNumber;
    double balance;
    string accountType;

public:
    Account(string type) : accountType(type), balance(0.0) {
        accountNumber = generateAccountNumber(); // Generate a unique account number
    }

    void deposit(double amount) {
        balance += amount; // Add to balance
        // Logic to record the transaction
    }

    bool withdraw(double amount) {
        if (amount <= balance) {
            balance -= amount; // Deduct from balance
            // Logic to record the transaction
            return true; // Withdrawal successful
        }
        return false; // Insufficient funds
    }

    double checkBalance() {
        return balance; // Return current balance
    }
};

3. Transaction Class The Transaction class records transaction details.

class Transaction {
private:
    string transactionID;
    double amount;
    string transactionType;
    string date;

public:
    void recordTransaction(string type, double amt) {
        transactionType = type;
        amount = amt;
        date = getCurrentDate(); // Get the current date
        // Logic to store transaction details
    }
};

4. Admin Class (Optional) The Admin class can manage user accounts and system-level operations.

class Admin {
public:
    void viewAllUsers() {
        // Logic to retrieve and display all users
    }

    void deleteUser(string userID) {
        // Logic to delete a user by ID
    }
};

Example Usage User Registration and Login

User user;
user.registerUser("Alice", "strongPassword123");

if (user.login("strongPassword123")) {
    cout << "Login successful!" << endl;
} else {
    cout << "Invalid credentials." << endl;
}

Account Operations

Account savingsAccount("Savings");
savingsAccount.deposit(1000.0);

if (savingsAccount.withdraw(300.0)) {
    cout << "Withdrawal successful!" << endl;
} else {
    cout << "Insufficient funds." << endl;
}

cout << "Current Balance: $" << savingsAccount.checkBalance() << endl;

Transaction Management

Transaction transaction;
transaction.recordTransaction("Deposit", 1000.0);
transaction.recordTransaction("Withdrawal", 300.0);

Conclusion

By applying OOP principles, the Online Banking System can be developed in a structured manner, allowing for easy maintenance and scalability. Each class encapsulates its functionality, enhancing code reusability. You can extend this system further with features like multi-currency support, enhanced security measures, or a user-friendly interface.