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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  
20  package org.apache.myfaces.orchestra.conversation.jsf.components;
21  
22  import java.io.IOException;
23  
24  import javax.faces.component.UIComponentBase;
25  import javax.faces.context.FacesContext;
26  
27  import org.apache.myfaces.orchestra.conversation.ConversationRequestParameterProvider;
28  import org.apache.myfaces.shared_orchestra.renderkit.RendererUtils;
29  
30  /**
31   * Embedded links will start a new conversation context.
32   * <p>
33   * Use this as the ancestor of any clickable links that should cause the new page to
34   * run within a totally new set of conversations. This really only makes sense when
35   * those links cause a new window to open. That new window then acts completely
36   * independently of the original window (as long as data is stored in conversations,
37   * not directly in the http session).
38   * <p>
39   * Normally, all urls within a view are rendered with a query parameter holding the
40   * current conversation context id, causing a later request to that url to use the
41   * same context as was used to render the original page. This tag causes this special
42   * query parameter to be omitted for all urls output by nested components. When any
43   * such url is invoked, the missing conversation context id then causes a new
44   * conversation context to be created.
45   */
46  public class UISeparateConversationContext extends UIComponentBase
47  {
48      public static final String COMPONENT_FAMILY = "javax.faces.Component";
49      public static final String COMPONENT_TYPE = "org.apache.myfaces.orchestra.SeparateConversationContext";
50  
51      public void encodeBegin(FacesContext context) throws IOException
52      {
53          super.encodeBegin(context);
54  
55          // Stop appending the conversation context id to URLs. This means that a request using
56          // those urls will trigger a new conversation context rather than inheriting the one
57          // associated with this request.
58          ConversationRequestParameterProvider.setInSeparationMode(true);
59      }
60  
61      public void encodeChildren(FacesContext context) throws IOException
62      {
63          try
64          {
65              RendererUtils.renderChildren(context, this);
66          }
67          finally
68          {
69              // Restore the original separation mode. Actually, we just assume here that
70              // the original value was false. There's no reason for anyone to ever nest
71              // UISeparateConversationContext components, and nothing else fiddles with
72              // this flag so false is a reasonable assumption.
73              //
74              // TODO: actually save the original value?
75              ConversationRequestParameterProvider.setInSeparationMode(false);
76          }
77      }
78  
79      public boolean getRendersChildren()
80      {
81          return true;
82      }
83  
84      public String getFamily()
85      {
86          return COMPONENT_FAMILY;
87      }
88  }