001// Copyright 2007 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.internal.beaneditor;
016
017import org.apache.tapestry5.services.ValidationConstraintGenerator;
018import org.apache.tapestry5.services.Environment;
019import org.apache.tapestry5.services.PropertyEditContext;
020import org.apache.tapestry5.ioc.AnnotationProvider;
021import org.apache.tapestry5.ioc.Messages;
022import org.apache.tapestry5.ioc.internal.util.InternalUtils;
023
024import java.util.List;
025import java.util.Arrays;
026import java.util.regex.Pattern;
027
028/**
029 * Generates constraints from the containing component's property file.
030 * Looks for a key in the form: propertyId-validate. 
031 *
032 */
033public class MessagesConstraintGenerator implements ValidationConstraintGenerator
034{
035
036    private final Environment environment;
037    private final String format="%s-validate";
038    private final Pattern splitPattern;
039
040    public MessagesConstraintGenerator(final Environment environment) {
041        this.environment = environment;
042        splitPattern = Pattern.compile(ValidateAnnotationConstraintGenerator.VALIDATOR_PATTERN);
043    }
044
045    public List<String> buildConstraints(Class propertyType, AnnotationProvider annotationProvider)
046    {
047        EnvironmentMessages environmentMessages = environment.peek(EnvironmentMessages.class);
048        if (environmentMessages == null) {
049            return null;
050        }
051
052        String key = String.format(format,environmentMessages.getOverrideId());
053        Messages m = environmentMessages.getMessages();
054        if (!m.contains(key))
055        {
056            return null;
057        }
058
059        String result = m.get(key);
060        if (InternalUtils.isBlank(result))
061        {
062            return null;
063        }
064        return Arrays.asList(splitPattern.split(result));
065    }
066}