001    // Copyright 2005 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.tapestry.form.validator;
016    
017    import org.apache.tapestry.IMarkupWriter;
018    import org.apache.tapestry.IRequestCycle;
019    import org.apache.tapestry.TapestryUtils;
020    import org.apache.tapestry.form.FormComponentContributorContext;
021    import org.apache.tapestry.form.IFormComponent;
022    import org.apache.tapestry.form.ValidationMessages;
023    import org.apache.tapestry.util.RegexpMatcher;
024    import org.apache.tapestry.valid.ValidationConstraint;
025    import org.apache.tapestry.valid.ValidationStrings;
026    import org.apache.tapestry.valid.ValidatorException;
027    
028    /**
029     * Validates that the user input, a string, is an email address (by checking it against a regular
030     * expression).
031     * 
032     * @author Howard Lewis Ship
033     * @since 4.0
034     */
035    public class Email extends BaseValidator
036    {
037        static final String PATTERN = "^\\w[-._\\w]*\\w@\\w[-._\\w]*\\w\\.\\w{2,6}$";
038    
039        // TODO: Possible thread safety issue if the validator
040        // is shared across threads, because the matcher
041        // will be too.
042        private RegexpMatcher _matcher = new RegexpMatcher();
043    
044        public Email()
045        {
046        }
047    
048        public Email(String initializer)
049        {
050            super(initializer);
051        }
052    
053        public void validate(IFormComponent field, ValidationMessages messages, Object object)
054                throws ValidatorException
055        {
056            String input = (String) object;
057    
058            if (!_matcher.matches(PATTERN, input))
059                throw new ValidatorException(buildMessage(messages, field),
060                        ValidationConstraint.EMAIL_FORMAT);
061        }
062    
063        private String buildMessage(ValidationMessages messages, IFormComponent field)
064        {
065            return messages.formatValidationMessage(
066                    getMessage(),
067                    ValidationStrings.INVALID_EMAIL,
068                    new Object[]
069                    { field.getDisplayName() });
070        }
071    
072        public void renderContribution(IMarkupWriter writer, IRequestCycle cycle,
073                FormComponentContributorContext context, IFormComponent field)
074        {
075            context.includeClasspathScript("/org/apache/tapestry/form/validator/RegExValidator.js");
076    
077            String pattern = _matcher.getEscapedPatternString(PATTERN);
078            String message = TapestryUtils.enquote(buildMessage(context, field));
079    
080            StringBuffer buffer = new StringBuffer("function(event) { Tapestry.validate_regex(event, '");
081            buffer.append(field.getClientId());
082            buffer.append("', '");
083            buffer.append(pattern);
084            buffer.append("', ");
085            buffer.append(message);
086            buffer.append("); }");
087    
088            context.addSubmitHandler(buffer.toString());
089        }
090    }