public class CreditCard {
    private String cardNumber;
    private String cardHolderName;
    private String expirationMonthYear;
    private int cvv;

    public CreditCard() {} // Empty Constructor

    public void setCardNumber(String cardNumber) { 
        this.cardNumber = cardNumber; 
    }
    public void setCardHolderName(String cardHolderName) { 
        this.cardHolderName = cardHolderName; 
    }
    public void setExpirationMonthYear(String expirationMonthYear) { 
        this.expirationMonthYear = expirationMonthYear;
    }
    public void setCvv(int cvv) { 
        this.cvv = cvv; 
    }

    public String getCardNumber() { 
        return cardNumber; 
    }
    public String getCardHolderName() {
        return cardHolderName;
    }
    public String getExpirationMonthYear() {
        return expirationMonthYear; 
    }
    public int getCvv() {
        return cvv; 
    }
}

CreditCard card = new CreditCard();
card.setCardNumber("1234-5678-9012-3456");
card.setCardHolderName("Lilywhite Lilith");
card.setExpirationMonthYear("12/25");
card.setCvv(123);

public class CreditCard {
    private final String cardNumber;
    private final String cardHolderName;
    private final String expirationMonthYear;
    private final int cvv;

    public CreditCard(String cardNumber,
                      String cardHolderName,
                      String expirationMonthYear,
                      int cvv) {
        // 1. Identify essential attributes for object creation
        // 2. Create a constructor that accepts all essential attributes
        this.cardNumber = cardNumber;
        this.cardHolderName = cardHolderName;
        this.expirationMonthYear = expirationMonthYear;
        this.cvv = cvv;
    }

    // 3. Remove setter and getter methods 

    // Find real behavior related to credit card usage

}

// 4. Update object creation calls to pass all required attributes upfront
CreditCard card = new CreditCard("1234-5678-9012-3456",
                                 "Lilywhite Lilith", 
                                 "12/25", 
                                 123);