001 // Copyright 2007, 2008, 2010 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
015 package org.apache.tapestry5.internal.services;
016
017 import org.apache.tapestry5.json.JSONObject;
018 import org.apache.tapestry5.services.javascript.InitializationPriority;
019 import org.apache.tapestry5.services.javascript.StylesheetLink;
020
021 /**
022 * Responsible for injecting script and style links into the <head> and <body> element of the rendered HTML
023 * document.
024 */
025 public interface DocumentLinker
026 {
027 /**
028 * Adds a link to load a JavaScript library. . The <script> elements will be added inside
029 * the document's <head>.
030 */
031 void addScriptLink(String scriptURL);
032
033 /**
034 * Adds a link to load a CSS stylesheet.
035 */
036 void addStylesheetLink(StylesheetLink stylesheet);
037
038 /**
039 * Adds JavaScript code. The code is collected into a single block that is injected just before the close body tag
040 * of the page (in a full page render) and collected as the "script" property of the partial page render response.
041 * The JavaScript is executed after the page loads (or in an Ajax update, after external JavaScript libraries are
042 * loaded and the DOM is updated).
043 * <p>
044 * This method may be called multiple times for the same priority and the script will be accumulated.
045 *
046 * @param priority
047 * when to execute the provided script
048 * @param script
049 * statement to add to the block (a newline will be appended as well)
050 */
051 void addScript(InitializationPriority priority, String script);
052
053 /**
054 * Adds a call to the Tapestry.init() function. This may be called multiple times and the init() calls will occur
055 * in order. In a normal page render, the init() calls will be added to the main JavaScript block, but in a partial
056 * page render Ajax response, the initialization will be property "init" of the partial page render response.
057 * <p>
058 * This method should only be invoked at most once per priority.
059 *
060 * @since 5.2.0
061 */
062 void setInitialization(InitializationPriority priority, JSONObject initialization);
063 }