001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.wicket.bean.validation;
018
019import java.util.Locale;
020
021import javax.validation.MessageInterpolator;
022
023import org.apache.wicket.Session;
024import org.apache.wicket.util.lang.Args;
025
026/**
027 * {@link MessageInterpolator} that adapts another to a locale from Wicket's {@link Session}
028 * 
029 * @author igor
030 */
031public class SessionLocaleInterpolator implements MessageInterpolator
032{
033        private final MessageInterpolator delegate;
034
035        /**
036         * Constructor
037         * 
038         * @param delegate
039         *            the MessageInterpolator to delegate to
040         */
041        public SessionLocaleInterpolator(MessageInterpolator delegate)
042        {
043                Args.notNull(delegate, "delegate");
044                this.delegate = delegate;
045        }
046
047        @Override
048        public String interpolate(final String messageTemplate,
049                final MessageInterpolator.Context context)
050        {
051                final Locale locale = getLocale();
052                if (locale != null)
053                {
054                        return interpolate(messageTemplate, context, locale);
055                }
056                else
057                {
058                        return delegate.interpolate(messageTemplate, context);
059                }
060        }
061
062        @Override
063        public String interpolate(final String message, final MessageInterpolator.Context context,
064                final Locale locale)
065        {
066                return delegate.interpolate(message, context, locale);
067        }
068
069        private Locale getLocale()
070        {
071                return Session.exists() ? Session.get().getLocale() : null;
072        }
073}