1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.myfaces.trinidad.render;
20
21 import java.io.IOException;
22
23 import javax.faces.FacesException;
24 import javax.faces.component.UIViewRoot;
25 import javax.faces.context.FacesContext;
26
27 /**
28 * An InternalView is a view ID that is handled internally to the webapp,
29 * without (necessarily) dispatching to an external resource. This
30 * can also be used to register pseudo-URLs that
31 * <p>
32 * InternalViews should be registered with a .properties-syntax file at
33 * <code>/META-INF/org.apache.myfaces.trinidad.render.InternalView.properties</code>
34 */
35 public abstract class InternalView
36 {
37 /**
38 * Creates the UIViewRoot.
39 * <p>
40 * Unlike ViewHandler.createView(), null is an acceptable return value -
41 * it indicates that a default, empty UIViewRoot for this viewId should be
42 * created on behalf of the InternalView, which might populate the
43 * view during renderView().
44 */
45 abstract public UIViewRoot createView(FacesContext context, String viewId);
46
47 /**
48 * Restores the UIViewRoot; return null if no view should be returned.
49 */
50 abstract public UIViewRoot restoreView(FacesContext context, String viewId);
51
52 /**
53 * Renders the view.
54 */
55 abstract public void renderView(
56 FacesContext context,
57 UIViewRoot viewToRender) throws IOException, FacesException;
58
59
60 /**
61 * Return true if this view is stateless; which, by default, it is.
62 * Stateless views will have no state saved during Render Response.
63 * restoreView() will still be called, so a stateless view can
64 * still process postback by returning a populated component tree
65 * from restoreView().
66 */
67 public boolean isStateless(FacesContext context, String viewId)
68 {
69 return true;
70 }
71 }
72