Java Credit Card Number Validator

RegexCardValidator.java

package net.bubblemix.cardcheck;

/**
 * Validator for credit card numbers
 * Checks validity and returns card type
 * 
 * @author ian.chen
 */
public class RegexCardValidator {
    
    /**
     * Checks if the field is a valid credit card number.
     * @param card The card number to validate.
     * @return Whether the card number is valid.
     */
    public static CardValidationResult isValid(final String cardIn) {
        String card = cardIn.replaceAll("[^0-9]+", ""); // remove all non-numerics
        if ((card == null) || (card.length() < 13) || (card.length() > 19)) {
            return new CardValidationResult(card,"failed length check");
        }

        if (!luhnCheck(card)) {
            return new CardValidationResult(card,"failed luhn check");
        }

        CardCompany cc = CardCompany.gleanCompany(card);
        if (cc == null) return new CardValidationResult(card,"failed card company check");
        
        return new CardValidationResult(card,cc);
    }

    /**
     * Checks for a valid credit card number.
     * @param cardNumber Credit Card Number.
     * @return Whether the card number passes the luhnCheck.
     */
    protected static boolean luhnCheck(String cardNumber) {
        // number must be validated as 0..9 numeric first!!
        int digits = cardNumber.length();
        int oddOrEven = digits & 1;
        long sum = 0;
        for (int count = 0; count < digits; count++) {
            int digit = 0;
            try {
                digit = Integer.parseInt(cardNumber.charAt(count) + "");
            } catch(NumberFormatException e) {
                return false;
            }

            if (((count & 1) ^ oddOrEven) == 0) { // not
                digit *= 2;
                if (digit > 9) {
                    digit -= 9;
                }
            }
            sum += digit;
        }

        return (sum == 0) ? false : (sum % 10 == 0);
    }
    
    /**
     * Run some tests to show this works
     * @param args
     */
    public static void main(String[] args) {
        String visa = "4444444444444448";
        String master = "5500005555555559";
        String amex = "371449635398431";
        String diners = "36438936438936";
        String discover = "6011016011016011";
        String jcb = "3566003566003566";
        String luhnFail = "1111111111111111";
        
        String invalid = "abcdabcdabcdabcd";
        
        printTest(visa);
        printTest(master);
        printTest(amex);
        printTest(diners);
        printTest(discover);
        printTest(jcb);
        printTest(invalid);
        printTest(luhnFail);

    }

    /**
     * Check a card number and print the result
     * @param cardIn
     */
    private static void printTest(String cardIn) {
        CardValidationResult result = RegexCardValidator.isValid(cardIn);
        System.out.println(result.isValid() + " : " + (result.isValid()? result.getCardType().getIssuerName(): "")  + " : " + result.getMessage() );
    }
}

CardCompany.java

package net.bubblemix.cardcheck;

/**
 * enum for card company specifics
 * 
 */
public enum CardCompany {

    VISA ("^4[0-9]{12}(?:[0-9]{3})?$", "VISA"),
    MASTERCARD ("^5[1-5][0-9]{14}$", "MASTER"),
    AMEX ("^3[47][0-9]{13}$", "AMEX"),
    DINERS ("^3(?:0[0-5]|[68][0-9])[0-9]{11}$", "Diners"),
    DISCOVER ("^6(?:011|5[0-9]{2})[0-9]{12}$", "DISCOVER"),
    JCB ("^(?:2131|1800|35\\d{3})\\d{11}$", "JCB");

    private String regex;
    private String issuerName;

    CardCompany(String regex, String issuerName) {
        this.regex = regex;
        this.issuerName = issuerName;
    }

    public boolean matches(String card) {
        return card.matches(this.regex);
    }
    
    public String getIssuerName() {
        return this.issuerName;
    }
    
    /**
     * get an enum from a card number
     * @param card
     * @return
     */
    public static CardCompany gleanCompany(String card) {
        for (CardCompany cc : CardCompany.values()){
            if (cc.matches(card)) {
                return cc;
            }
        }
        return null;
    }

    /**
     * get an enum from an issuerName
     * @param issuerName
     * @return
     */
    public static CardCompany gleanCompanyByIssuerName(String issuerName) {
        for (CardCompany cc : CardCompany.values()){
            if (cc.getIssuerName().equals(issuerName)) {
                return cc;
            }
        }
        return null;
    }
}

CardValidationResult.java

package net.bubblemix.cardcheck;

/**
 * Container for validation result
 */
public class CardValidationResult {
    private boolean valid;
    private CardCompany cardType;
    private String error;
    private String cardNo;

    public CardValidationResult(String cardNo, String error) {
        this.cardNo = cardNo;
        this.error = error;
    }
    public CardValidationResult(String cardNo, CardCompany cardType) {
        this.cardNo = cardNo;
        this.valid = true;
        this.cardType = cardType;
    }
    public boolean isValid() {
        return valid;
    }
    public CardCompany getCardType() {
        return cardType;
    }
    public String getError() {
        return error;
    }
    public String cardNo() {
        return this.cardNo;
    }
    public String getMessage() {
        return cardNo + "    >>    " + ((valid) ? ("card: " + this.cardType ): error) ;
    }
}