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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  }