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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.mina.codec.delimited.serialization;
21  
22  import java.io.IOException;
23  import java.io.ObjectOutputStream;
24  import java.io.Serializable;
25  import java.nio.ByteBuffer;
26  
27  import org.apache.mina.codec.delimited.ByteBufferEncoder;
28  import org.apache.mina.util.ByteBufferOutputStream;
29  
30  /**
31   * Encoder providing the built-in Java-serialization.
32   * 
33   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
34   */
35  public class JavaNativeMessageEncoder<OUT extends Serializable> extends ByteBufferEncoder<OUT> {
36      @Override
37      public ByteBuffer encode(OUT message) {
38          // avoid the copy done in Transcoder
39          return serialize(message);
40      }
41  
42      private OUT lastObject;
43  
44      private ByteBuffer lastSerialized;
45  
46      @Override
47      public int getEncodedSize(OUT message) {
48          return serialize(message).remaining();
49      }
50  
51      private ByteBuffer serialize(OUT message) {
52          if (message != lastObject) {
53              ByteBufferOutputStream ebbosa = new ByteBufferOutputStream();
54              ebbosa.setElastic(true);
55              try {
56                  ObjectOutputStream oos = new ObjectOutputStream(ebbosa);
57                  oos.writeObject(message);
58                  oos.close();
59                  lastObject = message;
60                  lastSerialized = ebbosa.getByteBuffer();
61              } catch (IOException e) {
62                  throw new IllegalStateException("Serialization exception", e);
63              }
64          }
65          return lastSerialized;
66      }
67  
68      @Override
69      public void writeTo(OUT message, ByteBuffer buffer) {
70          buffer.put(serialize(message));
71      }
72  }