    001// Copyright 2006, 2007, 2008, 2009, 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.ComponentResourcesCommon;
    018import org.apache.tapestry5.internal.structure.Page;
    019import org.apache.tapestry5.services.pageload.ComponentResourceSelector;
    020
    021/**
    022 * Instantiates a fully loaded, configured instance of a Tapestry page. This is a recursive process, since part of
    023 * loading a page is to load the page elements for the page, many of which are components. Further, in some cases, the
    024 * full component tree is not identified until after each component's template is loaded. Pages are instantiated once
    025 * for each {@link ComponentResourceSelector} (prior to 5.3, once for each locale; prior to 5.1, for locale and pooled).
    026 *
    027 * @see RequestPageCache
    028 */
    029public interface PageLoader
    030{
    031    /**
    032     * Loads the page for the indicated selector.
    033     *
    034     * @param pageName
    035     *            the <em>canonicalized</em> logical name of the page, which will be made available via
    036     *            {@link Page#getName()} and {@link ComponentResourcesCommon#getPageName()} (for any component within
    037     *            the page).
    038     * @param selector
    039     *            Encapsulates the locale and other information used to select the component's
    040     *            template and message catalog resources.
    041     */
    042    Page loadPage(String pageName, ComponentResourceSelector selector);
    043}