001// Copyright 2007-2013 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
015package org.apache.tapestry5.validator;
016
017import org.apache.tapestry5.Field;
018import org.apache.tapestry5.MarkupWriter;
019import org.apache.tapestry5.ValidationException;
020import org.apache.tapestry5.commons.MessageFormatter;
021import org.apache.tapestry5.services.FormSupport;
022import org.apache.tapestry5.services.javascript.DataConstants;
023import org.apache.tapestry5.services.javascript.JavaScriptSupport;
024
025/**
026 * Validates that a string value has not exceeded a maximum length.
027 */
028public final class MaxLength extends AbstractValidator<Integer, String>
029{
030    public MaxLength(JavaScriptSupport javaScriptSupport)
031    {
032        super(Integer.class, String.class, "maximum-string-length", javaScriptSupport);
033    }
034
035    public void validate(Field field, Integer constraintValue, MessageFormatter formatter, String value)
036            throws ValidationException
037    {
038        if (value.length() > constraintValue)
039            throw new ValidationException(buildMessage(formatter, field, constraintValue));
040    }
041
042    private String buildMessage(MessageFormatter formatter, Field field, Integer constraintValue)
043    {
044        return formatter.format(constraintValue, field.getLabel());
045    }
046
047    public void render(Field field, Integer constraintValue, MessageFormatter formatter, MarkupWriter writer,
048                       FormSupport formSupport)
049    {
050        if (formSupport.isClientValidationEnabled())
051        {
052            javaScriptSupport.require("t5/core/validation");
053
054            writer.attributes(DataConstants.VALIDATION_ATTRIBUTE, true,
055                    "data-validate-max-length", constraintValue.toString(),
056                    "data-max-length-message", buildMessage(formatter, field, constraintValue));
057        }
058    }
059}