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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  package org.apache.myfaces.trinidad.util;
20  
21  import java.io.Serializable;
22  
23  /**
24   * Holds an unserializable value in a transient variable so that
25   * unserializable Objects can be safely placed in distributed Sessions
26   * without blowing up.  Users should expect that getValue() will return
27   * <code>null</code> if the class has been serialized/de-serialized
28   */ 
29  public final class TransientHolder<T> implements Serializable 
30  { 
31    private TransientHolder(T value) 
32    { 
33      _value = value; 
34    } 
35      
36    public static <T> TransientHolder<T> newTransientHolder(T held)
37    {
38      return new TransientHolder<T>(held);
39    }
40    
41    public T getValue() 
42    { 
43      return _value; 
44    } 
45   
46    private final transient T _value; 
47    private static final long serialVersionUID = 1L; 
48  }