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
015package org.apache.tapestry.form.validator;
016
017import org.apache.tapestry.IMarkupWriter;
018import org.apache.tapestry.IRequestCycle;
019import org.apache.tapestry.TapestryUtils;
020import org.apache.tapestry.form.FormComponentContributorContext;
021import org.apache.tapestry.form.IFormComponent;
022import org.apache.tapestry.form.ValidationMessages;
023import org.apache.tapestry.valid.ValidationConstraint;
024import org.apache.tapestry.valid.ValidationStrings;
025import org.apache.tapestry.valid.ValidatorException;
026
027/**
028 * Validator that ensures a string value does not exceed a maximum length.
029 * 
030 * @author Howard Lewis Ship
031 * @since 4.0
032 */
033public class MaxLength extends BaseValidator
034{
035    private int _maxLength;
036
037    public MaxLength()
038    {
039
040    }
041
042    public MaxLength(String initializer)
043    {
044        super(initializer);
045    }
046
047    public void setMaxLength(int maxLength)
048    {
049        _maxLength = maxLength;
050    }
051
052    public void validate(IFormComponent field, ValidationMessages messages, Object object)
053            throws ValidatorException
054    {
055        String string = (String) object;
056
057        if (string.length() > _maxLength)
058            throw new ValidatorException(buildMessage(messages, field),
059                    ValidationConstraint.MAXIMUM_WIDTH);
060    }
061
062    protected String buildMessage(ValidationMessages messages, IFormComponent field)
063    {
064        return messages.formatValidationMessage(
065                getMessage(),
066                ValidationStrings.VALUE_TOO_LONG,
067                new Object[]
068                { new Integer(_maxLength), field.getDisplayName() });
069    }
070
071    public void renderContribution(IMarkupWriter writer, IRequestCycle cycle,
072            FormComponentContributorContext context, IFormComponent field)
073    {
074        context.includeClasspathScript("/org/apache/tapestry/form/validator/StringValidator.js");
075
076        StringBuffer buffer = new StringBuffer("function(event) { Tapestry.validate_max_length(event, '");
077        buffer.append(field.getClientId());
078        buffer.append("', ");
079        buffer.append(_maxLength);
080        buffer.append(", ");
081        buffer.append(TapestryUtils.enquote(buildMessage(context, field)));
082        buffer.append("); }");
083
084        context.addSubmitHandler(buffer.toString());
085    }
086
087}