Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You 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 org.apache.commons.validator.util.Flags; /** * Perform credit card validations. * * <p> * By default, all supported card types are allowed. You can specify which * cards should pass validation by configuring the validation options. For * example, * </p> * * <pre> * <code>CreditCardValidator ccv = new CreditCardValidator(CreditCardValidator.AMEX + CreditCardValidator.VISA);</code> * </pre> * * <p> * 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> * * <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>. * </p> * * @version $Revision: 1739358 $ * @since Validator 1.1 * @deprecated Use the new CreditCardValidator in the routines package. This class * will be removed in a future release. */ // CHECKSTYLE:OFF (deprecated code) @Deprecated 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. * <pre> * <code> * CreditCardValidator v = new CreditCardValidator(CreditCardValidator.NONE); * v.addAllowedCardType(customType); * v.isValid(aCardNumber); * </code> * </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<CreditCardType> cardTypes = new ArrayList<CreditCardType>(); /** * Create a new CreditCardValidator with default options. */ public CreditCardValidator() { this(AMEX + VISA + MASTERCARD + DISCOVER); } /** * Creates 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; } for (Object cardType : this.cardTypes) { CreditCardType type = (CreditCardType) cardType; if (type.matches(card)) { return true; } } return false; } /** * Adds 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); } /** * Change to support Visa Carte Blue used in France * has been removed - see Bug 35926 */ private static class Visa implements CreditCardType { private static final String PREFIX = "4"; @Override public boolean matches(String card) { return (card.substring(0, 1).equals(PREFIX) && (card.length() == 13 || card.length() == 16)); } } private static 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.contains(prefix2)) && (card.length() == 15)); } } private static 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 static 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.contains(prefix2)) && (card.length() == 16)); } } }