| /* |
| * Copyright 1999-2004 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.cocoon.woody.datatype.validationruleimpl; |
| |
| import org.apache.cocoon.woody.datatype.ValidationError; |
| import org.apache.cocoon.woody.util.I18nMessage; |
| import org.apache.cocoon.woody.Constants; |
| import org.outerj.expression.ExpressionContext; |
| |
| /** |
| * Performs the so called "mod 10" algorithm to check the validity of credit card numbers |
| * such as VISA. |
| * |
| * <p>In addition to this, the credit card number can be further validated by its length |
| * and prefix, but those properties are depended on the credit card type and such validation |
| * is not performed by this validation rule. |
| * |
| * @version $Id: Mod10ValidationRule.java,v 1.4 2004/03/05 13:02:30 bdelacretaz Exp $ |
| */ |
| public class Mod10ValidationRule extends AbstractValidationRule { |
| public ValidationError validate(Object value, ExpressionContext expressionContext) { |
| String numberToCheck = (String)value; |
| int nulOffset = '0'; |
| int sum = 0; |
| for (int i = 1; i <= numberToCheck.length(); i++) { |
| int currentDigit = numberToCheck.charAt(numberToCheck.length() - i) - nulOffset; |
| if ((i % 2) == 0) { |
| currentDigit *= 2; |
| currentDigit = currentDigit > 9 ? currentDigit - 9 : currentDigit; |
| sum += currentDigit; |
| } else { |
| sum += currentDigit; |
| } |
| } |
| if(!((sum % 10) == 0)) |
| return hasFailMessage() ? getFailMessage() : new ValidationError(new I18nMessage("validation.mod10", Constants.I18N_CATALOGUE)); |
| else |
| return null; |
| } |
| |
| public boolean supportsType(Class clazz, boolean arrayType) { |
| return String.class.isAssignableFrom(clazz) && !arrayType; |
| } |
| } |