1 /**
2 * This file Copyright (c) 2008-2013 Magnolia International
3 * Ltd. (http://www.magnolia-cms.com). All rights reserved.
4 *
5 *
6 * This file is dual-licensed under both the Magnolia
7 * Network Agreement and the GNU General Public License.
8 * You may elect to use one or the other of these licenses.
9 *
10 * This file is distributed in the hope that it will be
11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A
13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14 * Redistribution, except as permitted by whichever of the GPL
15 * or MNA you select, is prohibited.
16 *
17 * 1. For the GPL license (GPL), you can redistribute and/or
18 * modify this file under the terms of the GNU General
19 * Public License, Version 3, as published by the Free Software
20 * Foundation. You should have received a copy of the GNU
21 * General Public License, Version 3 along with this program;
22 * if not, write to the Free Software Foundation, Inc., 51
23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24 *
25 * 2. For the Magnolia Network Agreement (MNA), this file
26 * and the accompanying materials are made available under the
27 * terms of the MNA which accompanies this distribution, and
28 * is available at http://www.magnolia-cms.com/mna.html
29 *
30 * Any modifications to this file must keep this entire header
31 * intact.
32 *
33 */
34 package info.magnolia.rendering.model;
35
36 import javax.jcr.Node;
37
38 import info.magnolia.jcr.util.ContentMap;
39 import info.magnolia.rendering.template.RenderableDefinition;
40
41
42 /**
43 * A RenderingModel is used during rendering, it is analogous to the model part of the MVC pattern. It is associated with
44 * a renderable and is executed before a content node using the renderable is rendered. The renderer instantiates the
45 * RenderingModel and calls its execute method. While rendering the model is available to the template script under the
46 * name <code>model</code> and the value returned by the execute method is available under the name
47 * <code>actionResult</code>. It is commonly used to add backing logic to a component.
48 *
49 * <h3>Instantiation</h3>
50 * It is created using reflection for each renderable and used only once, its constructor can declare as arguments any
51 * components that can be provided by the current ComponentProvider and in addition it can declare any of the following
52 * constructor arguments:
53 * <ul>
54 * <li>Node the node that is currently being rendered</li>
55 * <li>RenderableDefinition the renderable definition begin used to render the node</li>
56 * <li>RenderingModel the rendering model of the parent renderable</li>
57 * </ul>
58 *
59 * After instantiation all request parameters are then mapped to the model's properties.
60 *
61 * <p>It can also abort the rendering by returning {@link #SKIP_RENDERING} from its execute method.</p>
62 *
63 * @param <RD> - an instance of {@link RenderableDefinition}
64 * @version $Id$
65 */
66 public interface RenderingModel <RD extends RenderableDefinition> {
67
68 /**
69 * A constant used in some special cases where rendering must be skipped, i.e. a redirect template.
70 * It can be used by template models as a return value for the {@link RenderingModel#execute()} method to inform
71 * {@link info.magnolia.rendering.renderer.AbstractRenderer} that it should not render anything in that particular
72 * case.
73 */
74 public static final String SKIP_RENDERING = "skip-rendering";
75
76 /**
77 * The model of the parent component or template.
78 */
79 RenderingModel< ? > getParent();
80
81 /**
82 * The content node tied to this model.
83 */
84 Node getNode();
85
86 /**
87 * Map representation of the content node tied to this model.
88 */
89 ContentMap getContent();
90
91 /**
92 * The renderable (template, area or component) tied to this model.
93 */
94 RD getDefinition();
95
96 /**
97 * Called after all properties were set. Can return a string which is passed
98 * to the method.
99 * {@link RenderableDefinition#determineTemplatePath(String, RenderingModel)}
100 */
101 String execute();
102
103 /**
104 * The top root model of the rendering process.
105 * In for example the scope of rendering a page this would be the pages model.
106 */
107 RenderingModel<?> getRoot();
108
109 }