/**

  * Copyright (C) 2006 Philipp Mpalampanis

  *

  * License: MPL 1.1/GPL 2.0/LGPL 2.1

  *

  * The contents of this file are subject to the Mozilla Public License Version

  * 1.1 (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.mozilla.org/MPL/

  *

  * Software distributed under the License is distributed on an "AS IS" basis,

  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License

  * for the specific language governing rights and limitations under the

  * License.

  *

  * Alternatively, the contents of this file may be used under the terms of

  * either the GNU General Public License Version 2 or later (the "GPL"), or

  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),

  * in which case the provisions of the GPL or the LGPL are applicable instead

  * of those above. If you wish to allow use of your version of this file only

  * under the terms of either the GPL or the LGPL, and not to allow others to

  * use your version of this file under the terms of the MPL, indicate your

  * decision by deleting the provisions above and replace them with the notice

  * and other provisions required by the GPL or the LGPL. If you do not delete

  * the provisions above, a recipient may use your version of this file under

  * the terms of any one of the MPL, the GPL or the LGPL.

  */

 package net.sf.echobinding.validation;

 import java.util.regex.Pattern;

 /**

  * A validator the uses a regular expression to validate user input. 

  *

  */

 public class RegexValidator implements Validator {

         private Pattern _pattern;

         private String _regex;

         /**

          * Constructs the regular expression validator.

          * 

          * @param regex - the regular expression to use

          */

         public RegexValidator(String regex) {

                 _pattern = Pattern.compile(regex);

                 _regex = regex;

         }

         /**

          * Checks if the input string matches the regular expression.

          * 

          * @param input - the user input

          */

         public ValidationReport validate(Object bean, Object input) {

                 if(input == null)

                         return new ValidationReport(true, null);

                 boolean matches = _pattern.matcher(input.toString()).matches();

                 String message = null;

                 if(!matches)

                         message = "input must match pattern '"+_regex+"'";

                 return new ValidationReport(matches, message);

         }

 }