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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;
21  
22  import org.apache.mina.common.IdleStatus;
23  import org.apache.mina.common.IoHandler;
24  import org.apache.mina.common.IoHandlerAdapter;
25  import org.apache.mina.common.IoSession;
26  import org.apache.mina.example.sumup.message.AddMessage;
27  import org.apache.mina.example.sumup.message.ResultMessage;
28  import org.apache.mina.util.SessionLog;
29  
30  /**
31   * {@link IoHandler} for SumUp server.
32   * 
33   * @author The Apache Directory Project (mina-dev@directory.apache.org)
34   * @version $Rev: 555855 $, $Date: 2007-07-13 12:19:00 +0900 (Fri, 13 Jul 2007) $
35   */
36  public class ServerSessionHandler extends IoHandlerAdapter {
37      public void sessionOpened(IoSession session) {
38          // set idle time to 60 seconds
39          session.setIdleTime(IdleStatus.BOTH_IDLE, 60);
40  
41          // initial sum is zero
42          session.setAttachment(new Integer(0));
43      }
44  
45      public void messageReceived(IoSession session, Object message) {
46          // client only sends AddMessage. otherwise, we will have to identify
47          // its type using instanceof operator.
48          AddMessage am = (AddMessage) message;
49  
50          // add the value to the current sum.
51          int sum = ((Integer) session.getAttachment()).intValue();
52          int value = am.getValue();
53          long expectedSum = (long) sum + value;
54          if (expectedSum > Integer.MAX_VALUE || expectedSum < Integer.MIN_VALUE) {
55              // if the sum overflows or underflows, return error message
56              ResultMessage rm = new ResultMessage();
57              rm.setSequence(am.getSequence()); // copy sequence
58              rm.setOk(false);
59              session.write(rm);
60          } else {
61              // sum up
62              sum = (int) expectedSum;
63              session.setAttachment(new Integer(sum));
64  
65              // return the result message
66              ResultMessage rm = new ResultMessage();
67              rm.setSequence(am.getSequence()); // copy sequence
68              rm.setOk(true);
69              rm.setValue(sum);
70              session.write(rm);
71          }
72      }
73  
74      public void sessionIdle(IoSession session, IdleStatus status) {
75          SessionLog.info(session, "Disconnecting the idle.");
76          // disconnect an idle client
77          session.close();
78      }
79  
80      public void exceptionCaught(IoSession session, Throwable cause) {
81          // close the connection on exceptional situation
82          session.close();
83      }
84  }