// Copyright 2008 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.tapestry5.validator;

 import org.apache.tapestry5.Field;

 import org.apache.tapestry5.MarkupWriter;

 import org.apache.tapestry5.ValidationException;

 import org.apache.tapestry5.ioc.MessageFormatter;

 import org.apache.tapestry5.services.FormSupport;

 import java.util.regex.Pattern;

 /**

  * A validator that checks if a given string is well-formed email address. This validator is not configurable.

  */

 public class Email extends AbstractValidator<Void, String>

 {

     private static final String ATOM = "[^\\x00-\\x1F^\\(^\\)^\\<^\\>^\\@^\\,^\\;^\\:^\\\\^\\\"^\\.^\\[^\\]^\\s]";

     private static final String DOMAIN = "(" + ATOM + "+(\\." + ATOM + "+)*";

     private static final String IP_DOMAIN = "\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\]";

     private static final Pattern PATTERN = Pattern

             .compile("^" + ATOM + "+(\\." + ATOM + "+)*@" + DOMAIN + "|" + IP_DOMAIN + ")$", Pattern.CASE_INSENSITIVE);

     public Email()

     {

         super(null, String.class, "invalid-email");

     }

     public void render(Field field, Void constraintValue, MessageFormatter formatter, MarkupWriter markupWriter,

                        FormSupport formSupport)

     {

     }

     private String buildMessage(MessageFormatter formatter, Field field)

     {

         return formatter.format(field.getLabel());

     }

     public void validate(Field field, Void constraintValue, MessageFormatter formatter, String value)

             throws ValidationException

     {

         if (!PATTERN.matcher(value).matches()) throw new ValidationException(buildMessage(formatter, field));

     }

 }