    001    // Copyright 2007, 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    /**
    024     * Validates that a string value has a minimum length.
    025     */
    026    public final class MinLength extends AbstractValidator<Integer, String>
    027    {
    028        public MinLength()
    029        {
    030            super(Integer.class, String.class, "minimum-string-length");
    031        }
    032
    033        public void validate(Field field, Integer constraintValue, MessageFormatter formatter, String value)
    034                throws ValidationException
    035        {
    036            if (value.length() < constraintValue)
    037                throw new ValidationException(buildMessage(formatter, field, constraintValue));
    038        }
    039
    040        private String buildMessage(MessageFormatter formatter, Field field, Integer constraintValue)
    041        {
    042            return formatter.format(constraintValue, field.getLabel());
    043        }
    044
    045        public void render(Field field, Integer constraintValue, MessageFormatter formatter, MarkupWriter writer,
    046                           FormSupport formSupport)
    047        {
    048            formSupport.addValidation(field, "minlength", buildMessage(formatter, field, constraintValue), constraintValue);
    049        }
    050    }