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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.example.sumup.codec;
21  
22  import org.apache.mina.core.buffer.IoBuffer;
23  import org.apache.mina.core.session.IoSession;
24  import org.apache.mina.example.sumup.message.AbstractMessage;
25  import org.apache.mina.example.sumup.message.AddMessage;
26  import org.apache.mina.filter.codec.ProtocolDecoderOutput;
27  import org.apache.mina.filter.codec.demux.MessageDecoder;
28  
29  /**
30   * A {@link MessageDecoder} that decodes {@link AddMessage}.
31   *
32   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
33   */
34  public class AddMessageDecoder extends AbstractMessageDecoder {
35  
36      public AddMessageDecoder() {
37          super(Constants.ADD);
38      }
39  
40      @Override
41      protected AbstractMessage decodeBody(IoSession session, IoBuffer in) {
42          if (in.remaining() < Constants.ADD_BODY_LEN) {
43              return null;
44          }
45  
46          AddMessage m = new AddMessage();
47          m.setValue(in.getInt());
48          return m;
49      }
50  
51      public void finishDecode(IoSession session, ProtocolDecoderOutput out)
52              throws Exception {
53      }
54  }