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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.filter.codec.serialization;
21  
22  import java.io.NotSerializableException;
23  import java.io.Serializable;
24  
25  import org.apache.mina.core.buffer.IoBuffer;
26  import org.apache.mina.core.session.IoSession;
27  import org.apache.mina.filter.codec.ProtocolEncoder;
28  import org.apache.mina.filter.codec.ProtocolEncoderAdapter;
29  import org.apache.mina.filter.codec.ProtocolEncoderOutput;
30  
31  /**
32   * A {@link ProtocolEncoder} which serializes {@link Serializable} Java objects
33   * using {@link IoBuffer#putObject(Object)}.
34   *
35   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
36   */
37  public class ObjectSerializationEncoder extends ProtocolEncoderAdapter {
38      private int maxObjectSize = Integer.MAX_VALUE; // 2GB
39  
40      /**
41       * Creates a new instance.
42       */
43      public ObjectSerializationEncoder() {
44          // Do nothing
45      }
46  
47      /**
48       * @return the allowed maximum size of the encoded object.
49       * If the size of the encoded object exceeds this value, this encoder
50       * will throw a {@link IllegalArgumentException}.  The default value
51       * is {@link Integer#MAX_VALUE}.
52       */
53      public int getMaxObjectSize() {
54          return maxObjectSize;
55      }
56  
57      /**
58       * Sets the allowed maximum size of the encoded object.
59       * If the size of the encoded object exceeds this value, this encoder
60       * will throw a {@link IllegalArgumentException}.  The default value
61       * is {@link Integer#MAX_VALUE}.
62       * 
63       * @param maxObjectSize the maximum size for an encoded object
64       */
65      public void setMaxObjectSize(int maxObjectSize) {
66          if (maxObjectSize <= 0) {
67              throw new IllegalArgumentException("maxObjectSize: " + maxObjectSize);
68          }
69  
70          this.maxObjectSize = maxObjectSize;
71      }
72  
73      /**
74       * {@inheritDoc}
75       */
76      public void encode(IoSession session, Object message, ProtocolEncoderOutput out) throws Exception {
77          if (!(message instanceof Serializable)) {
78              throw new NotSerializableException();
79          }
80  
81          IoBuffer buf = IoBuffer.allocate(64);
82          buf.setAutoExpand(true);
83          buf.putObject(message);
84  
85          int objectSize = buf.position() - 4;
86          if (objectSize > maxObjectSize) {
87              throw new IllegalArgumentException("The encoded object is too big: " + objectSize + " (> " + maxObjectSize
88                      + ')');
89          }
90  
91          buf.flip();
92          out.write(buf);
93      }
94  }