SelfSerializer


1   /*
2    * Copyright (c) 1998-2006 Caucho Technology -- all rights reserved
3    *
4    * This file is part of Resin(R) Open Source
5    *
6    * Each copy or derived work must preserve the copyright notice and this
7    * notice unmodified.
8    *
9    * Resin Open Source is free software; you can redistribute it and/or modify
10   * it under the terms of the GNU General Public License as published by
11   * the Free Software Foundation; either version 2 of the License, or
12   * (at your option) any later version.
13   *
14   * Resin Open Source is distributed in the hope that it will be useful,
15   * but WITHOUT ANY WARRANTY; without even the implied warranty of
16   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
17   * of NON-INFRINGEMENT.  See the GNU General Public License for more
18   * details.
19   *
20   * You should have received a copy of the GNU General Public License
21   * along with Resin Open Source; if not, write to the
22   *   Free SoftwareFoundation, Inc.
23   *   59 Temple Place, Suite 330
24   *   Boston, MA 02111-1307  USA
25   *
26   * @author Scott Ferguson
27   */
28  
29  package com.caucho.ejb.protocol;
30  
31  import com.caucho.ejb.RemoteExceptionWrapper;
32  import com.caucho.server.util.CauchoSystem;
33  import com.caucho.vfs.ReadStream;
34  import com.caucho.vfs.TempStream;
35  import com.caucho.vfs.WriteStream;
36  
37  import java.io.*;
38  import java.rmi.RemoteException  ;
39  /**
40   * Serializer for transfers inside a single JVM.
41   */
42  public class SelfSerializer {
43    TempStream trs;
44  
45    ReadStream is;
46    WriteStream os;
47    
48    ObjectInputStream ois;
49    ObjectOutputStream oos;
50    
51    public static SelfSerializer allocate()
52      throws RemoteException  
53    {
54      SelfSerializer ser = new SelfSerializer();
55  
56      ser.clear();
57  
58      return ser;
59    }
60  
61    /**
62     * Clears the buffers for the serializer
63     */
64    public void clear()
65      throws RemoteException  
66    {
67      try {
68        trs = new TempStream(null);
69        os = new WriteStream(trs);
70        oos = new ObjectOutputStream(os);
71        is = null;
72        ois = null;
73      } catch (Exception   e) {
74        throw new RemoteExceptionWrapper(e);
75      }
76    }
77  
78    /**
79     * Serializes the object to the temp stream.
80     *
81     * @param obj the object to serialize
82     */
83    public void write(Object   obj)
84      throws RemoteException  
85    {
86      try {
87        oos.writeObject(obj);
88      } catch (Exception   e) {
89        throw new RemoteExceptionWrapper(e);
90      }
91    }
92  
93    /**
94     * Reads an object from the serialized stream.
95     */
96    public Object   read()
97      throws RemoteException  
98    {
99      try {
100       if (is == null) {
101         oos.flush();
102         is = trs.openRead(true);
103         ois = new LoaderObjectInputStream(is);
104       }
105       
106       return ois.readObject();
107     } catch (Exception   e) {
108       throw new RemoteExceptionWrapper(e);
109     }
110   }
111 
112   /**
113    * Closes the streams.
114    */
115   public void close()
116   {
117     try {
118       InputStream is = this.is;
119       this.is = null;
120       OutputStream os = this.os;
121       this.os = null;
122       if (is != null)
123         is.close();
124       if (os != null)
125         os.close();
126     } catch (IOException e) {
127     }
128   }
129   
130   /**
131    * Extension class so the classes will be loaded by the proper
132    * class loader.
133    */
134   static class LoaderObjectInputStream extends ObjectInputStream {
135     ClassLoader   loader;
136     
137     LoaderObjectInputStream(InputStream is)
138       throws IOException, StreamCorruptedException
139     {
140       super(is);
141 
142       loader = Thread.currentThread().getContextClassLoader();
143     }
144 
145     /**
146      * Finds the specified class using the current class loader.
147      */
148     protected Class   resolveClass(ObjectStreamClass v)
149       throws IOException, ClassNotFoundException  
150     {
151       return CauchoSystem.loadClass(v.getName(), false, loader);
152     }
153   }
154 }
155
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