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# Whiteboarding Question: Payment Processing System

You are designing a payment processing system for an online store. The store supports multiple payment methods.

# Requirements:

The checkout system must be able to process any payment in the same way.
Each payment method must have a process(double amount) -> boolean function that:
- Takes an amount as input.
- Returns whether the payment was successful.
Different payment methods require different data to be created:
- PayPal needs an email and password.
- Credit Card needs a card number, CVV, and billing address.
- Bitcoin needs a wallet address.
The system should be easily extendable to support future payment methods.

# Task

Design and implement the classes required to make this example work. Your solution should:

Define a structure that ensures all payment methods can be handled the same way at checkout.
Ensure all payment methods follow a consistent structure.
Make it easy to add new payment methods without modifying existing code.

# Example Expected Usage:

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public static void checkout(PaymentMethod paymentMethod, double amount) {
    if (paymentMethod.process(amount)) {
        System.out.println("Payment successful!");
    } else {
        System.out.println("Payment failed!");
    }
}

public static void main(String[] args) {
    PaymentMethod paypalPayment = new PayPal("user@example.com", "securepassword");
    PaymentMethod creditCardPayment = new CreditCard("1234-5678-9012-3456", "123", "123 Main St");
    PaymentMethod bitcoinPayment = new Bitcoin("1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa");

    checkout(paypalPayment, 50.00);  
    checkout(creditCardPayment, 100.00);  
    checkout(bitcoinPayment, 200.00);  
}

# Expected Console Output:

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Processing PayPal payment of $50.0 for user@example.com
Payment successful!
Processing Credit Card payment of $100.0 for card 1234-5678-9012-3456
Payment successful!
Processing Bitcoin payment of $200.0 to wallet 1A1zP1eP5QGefi2DMPTfTL5SLmv7DivfNa
Payment successful!

Course Resources

# Whiteboarding Question: Payment Processing System

# Requirements:

# Task

# Example Expected Usage:

# Expected Console Output:

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