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.routines; import java.io.Serializable; import java.util.ArrayList; import java.util.List; import org.apache.commons.validator.routines.checkdigit.CheckDigit; import org.apache.commons.validator.routines.checkdigit.LuhnCheckDigit; /** * <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>. * * @version $Revision: 909009 $ $Date: 2010-02-11 14:59:45 +0000 (Qui, 11 Fev 2010) $ * @since Validator 1.4 */ public class CreditCardValidator implements Serializable { /** * 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> */ public static final long NONE = 0; /** * Option specifying that American Express cards are allowed. */ public static final long AMEX = 1 << 0; /** * Option specifying that Visa cards are allowed. */ public static final long VISA = 1 << 1; /** * Option specifying that Mastercard cards are allowed. */ public static final long MASTERCARD = 1 << 2; /** * Option specifying that Discover cards are allowed. */ public static final long DISCOVER = 1 << 3; /** * Option specifying that Diners cards are allowed. */ public static final long DINERS = 1 << 4; /** * The CreditCardTypes that are allowed to pass validation. */ private final List cardTypes = new ArrayList(); /** * Luhn checkdigit validator for the card numbers. */ private static final CheckDigit LUHN_VALIDATOR = LuhnCheckDigit.LUHN_CHECK_DIGIT; /** American Express (Amex) Card Validator */ public static final CodeValidator AMEX_VALIDATOR = new CodeValidator("^(3[47]\\d{13})$", LUHN_VALIDATOR); /** Diners Card Validator */ public static final CodeValidator DINERS_VALIDATOR = new CodeValidator("^(30[0-5]\\d{11}|36\\d{12})$", LUHN_VALIDATOR); /** Discover Card regular expressions */ private static final RegexValidator DISCOVER_REGEX = new RegexValidator( new String[] { "^(6011\\d{12})$", "^(65\\d{14})$" }); /** Discover Card Validator */ public static final CodeValidator DISCOVER_VALIDATOR = new CodeValidator(DISCOVER_REGEX, LUHN_VALIDATOR); /** Mastercard Card Validator */ public static final CodeValidator MASTERCARD_VALIDATOR = new CodeValidator("^(5[1-5]\\d{14})$", LUHN_VALIDATOR); /** Visa Card Validator */ public static final CodeValidator VISA_VALIDATOR = new CodeValidator("^(4)(\\d{12}|\\d{15})$", LUHN_VALIDATOR); /** * 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(long options) { super(); if (isOn(options, VISA)) { this.cardTypes.add(VISA_VALIDATOR); } if (isOn(options, AMEX)) { this.cardTypes.add(AMEX_VALIDATOR); } if (isOn(options, MASTERCARD)) { this.cardTypes.add(MASTERCARD_VALIDATOR); } if (isOn(options, DISCOVER)) { this.cardTypes.add(DISCOVER_VALIDATOR); } if (isOn(options, DINERS)) { this.cardTypes.add(DINERS_VALIDATOR); } } /** * Create a new CreditCardValidator with the specified {@link CodeValidator}s. * * @param creditCardValidators Set of valid code validators */ public CreditCardValidator(CodeValidator[] creditCardValidators) { if (creditCardValidators == null) { throw new IllegalArgumentException("Card validators are missing"); } for (CodeValidator creditCardValidator : creditCardValidators) { cardTypes.add(creditCardValidator); } } /** * 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() == 0) { return false; } for (int i = 0; i < cardTypes.size(); i++) { CodeValidator type = (CodeValidator) cardTypes.get(i); if (type.isValid(card)) { return true; } } return false; } /** * Checks if the field is a valid credit card number. * * @param card The card number to validate. * @return The card number if valid or <code>null</code> if invalid. */ public Object validate(String card) { if (card == null || card.length() == 0) { return null; } Object result = null; for (int i = 0; i < cardTypes.size(); i++) { CodeValidator type = (CodeValidator) cardTypes.get(i); result = type.validate(card); if (result != null) { return result; } } return null; } /** * Tests whether the given flag is on. If the flag is not a power of 2 * (ie. 3) this tests whether the combination of flags is on. * * @param options The options specified. * @param flag Flag value to check. * * @return whether the specified flag value is on. */ private boolean isOn(long options, long flag) { return (options & flag) > 0; } }