    001// Copyright 2006, 2007, 2008, 2011 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.services;
    016
    017import org.apache.tapestry5.ioc.Messages;
    018import org.apache.tapestry5.services.InvalidationEventHub;
    019import org.apache.tapestry5.services.UpdateListener;
    020import org.apache.tapestry5.services.pageload.ComponentResourceSelector;
    021
    022public interface MessagesSource extends InvalidationEventHub, UpdateListener
    023{
    024    /**
    025     * Used to obtain a {@link Messages} instance for a particular component, within a particular locale. If the
    026     * component extends from another component, then its localized properties will merge with its parent's properties
    027     * (with the subclass overriding the super class on any conflicts).
    028     *
    029     * @param bundle
    030     *            defines the set of properties files to read, as well as a series of parent bundles to extend and
    031     *            override
    032     * @param selector
    033     *            defines the locale and other axes used to locate the necessary resources
    034     * @return the message catalog for the bundle, for the indicated selector
    035     */
    036    Messages getMessages(MessagesBundle bundle, ComponentResourceSelector selector);
    037}