/*
* $Id: CreditCardValidator.java 280974 2005-09-15 00:06:59Z niallp $
* $Rev: 280974 $
* $Date: 2005-09-15 01:06:59 +0100 (Thu, 15 Sep 2005) $
*
* ====================================================================
* Copyright 2001-2005 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.validator;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import org.apache.commons.validator.util.Flags;
/**
* <p>
* Perform credit card validations.
* </p>
* <p>
* By default, all supported card types are allowed. You can specify which cards should pass validation by configuring
* the validation options. For example,<br/>
* <code>CreditCardValidator ccv = new CreditCardValidator(CreditCardValidator.AMEX + CreditCardValidator.VISA);</code>
* configures the validator to only pass American Express and Visa cards. If a card type is not directly supported by
* this class, you can implement the CreditCardType interface and pass an instance into the
* <code>addAllowedCardType</code> method.
* </p>
* For a similar implementation in Perl, reference Sean M. Burke's
* <a href="http://www.speech.cs.cmu.edu/~sburke/pub/luhn_lib.html">script</a>.
* More information is also available
* <a href="http://www.merriampark.com/anatomycc.htm">here</a>.
*
* @since Validator 1.1
*/
public class CreditCardValidator {
/**
* Option specifying that no cards are allowed. This is useful if
* you want only custom card types to validate so you turn off the
* default cards with this option. <br/>
*
* <pre>
* CreditCardValidator v = new CreditCardValidator(CreditCardValidator.NONE);
* v.addAllowedCardType(customType);
* v.isValid(aCardNumber);
* </pre>
*
* @since Validator 1.1.2
*/
public static final int NONE = 0;
/**
* Option specifying that American Express cards are allowed.
*/
public static final int AMEX = 1 << 0;
/**
* Option specifying that Visa cards are allowed.
*/
public static final int VISA = 1 << 1;
/**
* Option specifying that Mastercard cards are allowed.
*/
public static final int MASTERCARD = 1 << 2;
/**
* Option specifying that Discover cards are allowed.
*/
public static final int DISCOVER = 1 << 3;
/**
* The CreditCardTypes that are allowed to pass validation.
*/
private final Collection cardTypes = new ArrayList();
/**
* Create a new CreditCardValidator with default options.
*/
public CreditCardValidator() {
this(AMEX + VISA + MASTERCARD + DISCOVER);
}
/**
* Create a new CreditCardValidator with the specified options.
*
* @param options Pass in
* CreditCardValidator.VISA + CreditCardValidator.AMEX to specify that
* those are the only valid card types.
*/
public CreditCardValidator(int options) {
super();
Flags f = new Flags(options);
if (f.isOn(VISA)) {
this.cardTypes.add(new Visa());
}
if (f.isOn(AMEX)) {
this.cardTypes.add(new Amex());
}
if (f.isOn(MASTERCARD)) {
this.cardTypes.add(new Mastercard());
}
if (f.isOn(DISCOVER)) {
this.cardTypes.add(new Discover());
}
}
/**
* 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 boolean isValid(String card) {
if ((card == null) || (card.length() < 13) || (card.length() > 19)) {
return false;
}
if (!this.luhnCheck(card)) {
return false;
}
Iterator types = this.cardTypes.iterator();
while (types.hasNext()) {
CreditCardType type = (CreditCardType) types.next();
if (type.matches(card)) {
return true;
}
}
return false;
}
/**
* Add an allowed CreditCardType that participates in the card
* validation algorithm.
*
* @param type The type that is now allowed to pass validation.
* @since Validator 1.1.2
*/
public void addAllowedCardType(CreditCardType type) {
this.cardTypes.add(type);
}
/**
* Checks for a valid credit card number.
*
* @param cardNumber Credit Card Number.
* @return Whether the card number passes the luhnCheck.
*/
protected 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);
}
/**
* CreditCardType implementations define how validation is performed
* for one type/brand of credit card.
*
* @since Validator 1.1.2
*/
public interface CreditCardType {
/**
* Returns true if the card number matches this type of credit
* card. Note that this method is <strong>not</strong> responsible
* for analyzing the general form of the card number because <code>CreditCardValidator</code> performs those
* checks before
* calling this method. It is generally only required to valid the
* length and prefix of the number to determine if it's the correct
* type.
*
* @param card The card number, never null.
* @return true if the number matches.
*/
boolean matches(String card);
}
/**
* Augmented to support Visa Carte Blue used in France
*/
private class Visa implements CreditCardType {
private static final String PREFIX = "4,5,";
@Override
public boolean matches(String card) {
String prefix2 = card.substring(0, 1) + ",";
return ((PREFIX.indexOf(prefix2) != -1)
&& (card.length() == 13 || card.length() == 16));
}
}
private class Amex implements CreditCardType {
private static final String PREFIX = "34,37,";
@Override
public boolean matches(String card) {
String prefix2 = card.substring(0, 2) + ",";
return ((PREFIX.indexOf(prefix2) != -1) && (card.length() == 15));
}
}
private class Discover implements CreditCardType {
private static final String PREFIX = "6011";
@Override
public boolean matches(String card) {
return (card.substring(0, 4).equals(PREFIX) && (card.length() == 16));
}
}
private class Mastercard implements CreditCardType {
private static final String PREFIX = "51,52,53,54,55,";
@Override
public boolean matches(String card) {
String prefix2 = card.substring(0, 2) + ",";
return ((PREFIX.indexOf(prefix2) != -1) && (card.length() == 16));
}
}
}