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 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.ioc.MessageFormatter; 021import org.apache.tapestry5.services.FormSupport; 022 023public final class MaxLength extends AbstractValidator<Integer, String> 024{ 025 public MaxLength() 026 { 027 super(Integer.class, String.class, "maximum-string-length"); 028 } 029 030 public void validate(Field field, Integer constraintValue, MessageFormatter formatter, String value) 031 throws ValidationException 032 { 033 if (value.length() > constraintValue) 034 throw new ValidationException(buildMessage(formatter, field, constraintValue)); 035 } 036 037 private String buildMessage(MessageFormatter formatter, Field field, Integer constraintValue) 038 { 039 return formatter.format(constraintValue, field.getLabel()); 040 } 041 042 public void render(Field field, Integer constraintValue, MessageFormatter formatter, MarkupWriter writer, 043 FormSupport formSupport) 044 { 045 // TODO: write a maxlength attribute into the element? But that's only for 046 // textfield, not for textarea. 047 048 formSupport.addValidation(field, "maxlength", buildMessage(formatter, field, constraintValue), constraintValue); 049 } 050}