001    // Copyright 2008 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry5.validator;
016    
017    import org.apache.tapestry5.Field;
018    import org.apache.tapestry5.MarkupWriter;
019    import org.apache.tapestry5.ValidationException;
020    import org.apache.tapestry5.ioc.MessageFormatter;
021    import org.apache.tapestry5.services.FormSupport;
022    
023    import java.util.regex.Pattern;
024    
025    /**
026     * A validator that checks if a given string is well-formed email address. This validator is not configurable.
027     */
028    public class Email extends AbstractValidator<Void, String>
029    {
030        private static final String ATOM = "[^\\x00-\\x1F^\\(^\\)^\\<^\\>^\\@^\\,^\\;^\\:^\\\\^\\\"^\\.^\\[^\\]^\\s]";
031    
032        private static final String DOMAIN = "(" + ATOM + "+(\\." + ATOM + "+)*";
033    
034        private static final String IP_DOMAIN = "\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\]";
035    
036        private static final Pattern PATTERN = Pattern
037                .compile("^" + ATOM + "+(\\." + ATOM + "+)*@" + DOMAIN + "|" + IP_DOMAIN + ")$", Pattern.CASE_INSENSITIVE);
038    
039        public Email()
040        {
041            super(null, String.class, "invalid-email");
042        }
043    
044        public void render(Field field, Void constraintValue, MessageFormatter formatter, MarkupWriter markupWriter,
045                           FormSupport formSupport)
046        {
047        }
048    
049        private String buildMessage(MessageFormatter formatter, Field field)
050        {
051            return formatter.format(field.getLabel());
052        }
053    
054        public void validate(Field field, Void constraintValue, MessageFormatter formatter, String value)
055                throws ValidationException
056        {
057            if (!PATTERN.matcher(value).matches()) throw new ValidationException(buildMessage(formatter, field));
058        }
059    }