PayloadContainer


1   /*
2    * Copyright 2002 by
3    * <a HREF="http://www.coridan.com">Coridan</a>
4    * <a HREF="mailto: support@coridan.com ">support@coridan.com</a>
5    *
6    * The contents of this file are subject to the Mozilla Public License Version
7    * 1.1 (the "License"); you may not use this file except in compliance with the
8    * License.  You may obtain a copy of the License at
9    * http://www.mozilla.org/MPL/
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11   * Software distributed under the License is distributed on an "AS IS" basis,
12   * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13   * for the specific language governing rights and limitations under the
14   * License.
15   *
16   * The Original Code is "MantaRay" (TM).
17   *
18   * The Initial Developer of the Original Code is Amir Shevat.
19   * Portions created by the Initial Developer are Copyright (C) 2006
20   * Coridan Inc.  All Rights Reserved.
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26   * LGPL license (the "GNU LESSER GENERAL PUBLIC LICENSE"), in which case the
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33   * of this file under either the MPL or the GNU LESSER GENERAL PUBLIC LICENSE.
34   
35   *
36   * This library is free software; you can redistribute it and/or modify it
37   * under the terms of the MPL as stated above or under the terms of the GNU
38   * Lesser General Public License as published by the Free Software Foundation;
39   * either version 2.1 of the License, or any later version.
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41   * This library is distributed in the hope that it will be useful, but WITHOUT
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46  /*
47   * Created on 07/06/2004
48   *
49   * Manta LTD
50   */
51  package org.mr.core.protocol;
52  
53  
54  
55  import java.io.IOException  ;
56  import java.nio.ByteBuffer  ;
57  
58  import org.mr.core.util.byteable.ByteBufferFactory;
59  import org.mr.core.util.byteable.Byteable;
60  import org.mr.core.util.byteable.IncomingByteBufferPool;
61  
62  
63  /**
64   * PayloadContainer holds the payload of the manta bus message
65   * when needed (lazy) it will serialize the payload and dump the object 
66   * and vise versa 
67   * 
68   * @author Amir Shevat
69   *
70   */
71  public class PayloadContainer  {
72      
73      
74      // one of them should be null and the other not null
75      private Byteable payloadObject = null;
76      //private ByteBuffer serializedPayload = null;
77      private ByteBuffer   payloadBuffer = null;
78      private ByteBuffer   toReleaseBuffer = null;
79  
80      public PayloadContainer(Byteable payload){
81          payloadObject = payload;
82      }
83  
84      protected PayloadContainer(ByteBuffer   buffer){
85          this.payloadBuffer = buffer.slice();
86          this.toReleaseBuffer = buffer;
87      }
88      
89      /**
90       * @return Returns the payloadObject.
91       */
92      public final synchronized Byteable getPayloadObject() throws IOException   {
93          //if(payloadObject == null && serializedPayload!= null){
94          //  payloadObject= MessageTransformer.byteableFormBuffer(serializedPayload);
95          //  serializedPayload = null;
96          //}
97          if (this.payloadObject == null && this.payloadBuffer != null) {
98              this.payloadObject =
99                  MessageTransformer.byteableFormBuffer(this.payloadBuffer);
100             IncomingByteBufferPool.getInstance().release(this.toReleaseBuffer);
101         }
102         return payloadObject;
103     }
104     
105     /**
106      * @return Returns the serializedPayload.
107      */
108     public final synchronized ByteBuffer   getSerializedPayload() throws IOException   {
109         //if(serializedPayload == null ){
110         //  serializedPayload = MessageTransformer.byteableToBuffer(payloadObject ,MessageTransformer.messageBodyBufferPool );
111         //  payloadObject = null;
112         //}
113         //return serializedPayload.duplicate();
114         if (payloadObject == null && payloadBuffer != null) {
115             return payloadBuffer;
116         } else {
117             if(toReleaseBuffer ==null){
118                 if(payloadObject != null){
119                     synchronized(payloadObject){
120                         this.toReleaseBuffer = MessageTransformer.byteableToBuffer(payloadObject, MessageTransformer.messageBodyBufferPool);
121                     }   
122                 }else{
123                     this.toReleaseBuffer = MessageTransformer.byteableToBuffer(payloadObject, MessageTransformer.messageBodyBufferPool);
124                 }
125             }
126             
127             
128             return toReleaseBuffer;
129 //          return MessageTransformer.byteableToBuffer(payloadObject, MessageTransformer.messageBodyBufferPool);
130         }
131     }
132 
133     /**
134      * Release the payload buffer.  If payloadObject isn't null, then
135      * it was serialized into toReleaseBuffer (see
136      * PayloadContainer.getSerializedPayload()), and should be
137      * released by MessageTransformer.messageBodyBufferPool.
138      * Otherwise the toReleaseBuffer must have come from the network
139      * layer, and not yet parsed into a Byteable object.  In this case
140      * the pool used by the network layer is used to release the
141      * buffer (IncomingByteBufferPool).
142      */
143     private int releaseCount = 0;
144     public synchronized final void release() {
145         releaseCount++;
146         ByteBufferFactory pool = null;
147 
148         if (this.payloadObject != null) {
149             pool = MessageTransformer.messageBodyBufferPool;
150         } else {
151             pool = IncomingByteBufferPool.getInstance();
152         }
153 
154         if (this.toReleaseBuffer != null) {
155             pool.release(this.toReleaseBuffer);
156             // prevent 2 releases of same buffer
157             toReleaseBuffer = null;
158         }
159         
160     }
161 
162     public String   toString(){
163         StringBuffer   buff = new StringBuffer  ();
164         buff.append("{payload object = ");
165         buff.append(payloadObject);
166         //buff.append(" buffer = ");
167         //buff.append(serializedPayload);
168         buff.append("}");
169         return buff.toString();
170     }
171 
172     
173 
174 
175 }
176
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