    001// Copyright 2010-2013 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.commons.Resource;
    018import org.apache.tapestry5.internal.structure.Page;
    019import org.apache.tapestry5.services.dynamic.DynamicTemplate;
    020import org.apache.tapestry5.services.pageload.ComponentRequestSelectorAnalyzer;
    021import org.apache.tapestry5.services.pageload.ComponentResourceSelector;
    022
    023import java.util.Set;
    024
    025/**
    026 * Access to localized page instances (which are now shared singletons, starting in release 5.2).
    027 * This service is a wrapper around the {@link PageLoader} that caches the loaded pages.
    028 *
    029 * @since 5.2.0
    030 */
    031public interface PageSource
    032{
    033    /**
    034     * Clears the source's cache of loaded pages. This occurs when an outside change to the world invalidates
    035     * created page instances. Introduced to handle the case where a page has a {@link DynamicTemplate}, but the
    036     * underlying {@link Resource} is noticed to have changed.
    037     *
    038     * @since 5.3
    039     */
    040    void clearCache();
    041
    042    /**
    043     * Returns a loaded instance of the indicated page, using the Locale and other information
    044     * from the {@link ComponentResourceSelector} obtained from the {@link ComponentRequestSelectorAnalyzer}.
    045     *
    046     * @param canonicalPageName
    047     * @return existing, or newly created, page instance
    048     */
    049    Page getPage(String canonicalPageName);
    050
    051    /**
    052     * Returns all currently loaded pages. This will include any previously loaded pages not yet reclaimed by the
    053     * garbage collector, and may include the same page loaded for different {@link ComponentResourceSelector}s. This is needed
    054     * for reporting purposes only.
    055     *
    056     * @see org.apache.tapestry5.corelib.pages.PageCatalog
    057     * @since 5.3
    058     */
    059    Set<Page> getAllPages();
    060}