    001// Copyright 2006, 2008, 2009, 2010, 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.services.messages;
    016
    017import org.apache.tapestry5.commons.Messages;
    018import org.apache.tapestry5.commons.Resource;
    019import org.apache.tapestry5.commons.services.InvalidationEventHub;
    020import org.apache.tapestry5.ioc.annotations.NotLazy;
    021import org.apache.tapestry5.ioc.annotations.UsesOrderedConfiguration;
    022import org.apache.tapestry5.model.ComponentModel;
    023import org.apache.tapestry5.services.pageload.ComponentResourceSelector;
    024
    025import java.util.Locale;
    026
    027/**
    028 * Used to connect a Tapestry component to its message catalog, or to obtain the application catalog (that all
    029 * component message catalogs extend from). The application catalog is defined by the collection of {@link Resource}s
    030 * contributed to the service. In general, component libraries will contribute a Resource before the "AppCatalog"
    031 * resource (representing
    032 * the application message catalog, WEB-INF/app.properties) so that the application can override messages of the
    033 * component library.
    034 */
    035@UsesOrderedConfiguration(Resource.class)
    036public interface ComponentMessagesSource
    037{
    038    /**
    039     * Used to obtain a {@link Messages} instance for a particular component, within a particular locale. If the
    040     * component extends from another component, then its localized properties will merge with its parent's properties
    041     * (with the subclass overriding the super class on any conflicts).
    042     *
    043     * @param componentModel
    044     * @param locale
    045     * @return the message catalog for the component, in the indicated locale
    046     * @deprecated Deprecated in 5.3; use {@link #getMessages(ComponentModel, ComponentResourceSelector)} instead.
    047     */
    048    Messages getMessages(ComponentModel componentModel, Locale locale);
    049
    050    /**
    051     * Used to obtain a {@link Messages} instance for a particular component, using a particular selector. If the
    052     * component extends from another component, then its localized properties will merge with its parent's properties
    053     * (with the subclass overriding the super class on any conflicts).
    054     *
    055     * @param componentModel
    056     * @param selector       determined correct version of messages to obtain
    057     * @return the message catalog for the component, in the indicated selector
    058     * @since 5.3
    059     */
    060    Messages getMessages(ComponentModel componentModel, ComponentResourceSelector selector);
    061
    062    /**
    063     * Gets the Messages derived from the application's message catalog.
    064     *
    065     * @since 5.2.0
    066     */
    067    Messages getApplicationCatalog(Locale locale);
    068
    069    /**
    070     * Returns the event hub that allows listeners to be notified when any underlying message catalog file is changed.
    071     *
    072     * @since 5.1.0.0
    073     */
    074    @NotLazy
    075    InvalidationEventHub getInvalidationEventHub();
    076}