01: /*
02: * Licensed to the Apache Software Foundation (ASF) under one
03: * or more contributor license agreements. See the NOTICE file
04: * distributed with this work for additional information
05: * regarding copyright ownership. The ASF licenses this file
06: * to you under the Apache License, Version 2.0 (the
07: * "License"); you may not use this file except in compliance
08: * with the License. You may obtain a copy of the License at
09: *
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.slf4j.Logger;
29: import org.slf4j.LoggerFactory;
30:
31: /**
32: * {@link IoHandler} for SumUp server.
33: *
34: * @author The Apache MINA Project (dev@mina.apache.org)
35: * @version $Rev: 616100 $, $Date: 2008-01-28 15:58:32 -0700 (Mon, 28 Jan 2008) $
36: */
37: public class ServerSessionHandler extends IoHandlerAdapter {
38:
39: private static final String SUM_KEY = "sum";
40:
41: private final Logger logger = LoggerFactory.getLogger(getClass());
42:
43: @Override
44: public void sessionOpened(IoSession session) {
45: // set idle time to 60 seconds
46: session.getConfig().setIdleTime(IdleStatus.BOTH_IDLE, 60);
47:
48: // initial sum is zero
49: session.setAttribute(SUM_KEY, new Integer(0));
50: }
51:
52: @Override
53: public void messageReceived(IoSession session, Object message) {
54: // client only sends AddMessage. otherwise, we will have to identify
55: // its type using instanceof operator.
56: AddMessage am = (AddMessage) message;
57:
58: // add the value to the current sum.
59: int sum = ((Integer) session.getAttribute(SUM_KEY)).intValue();
60: int value = am.getValue();
61: long expectedSum = (long) sum + value;
62: if (expectedSum > Integer.MAX_VALUE
63: || expectedSum < Integer.MIN_VALUE) {
64: // if the sum overflows or underflows, return error message
65: ResultMessage rm = new ResultMessage();
66: rm.setSequence(am.getSequence()); // copy sequence
67: rm.setOk(false);
68: session.write(rm);
69: } else {
70: // sum up
71: sum = (int) expectedSum;
72: session.setAttribute(SUM_KEY, new Integer(sum));
73:
74: // return the result message
75: ResultMessage rm = new ResultMessage();
76: rm.setSequence(am.getSequence()); // copy sequence
77: rm.setOk(true);
78: rm.setValue(sum);
79: session.write(rm);
80: }
81: }
82:
83: @Override
84: public void sessionIdle(IoSession session, IdleStatus status) {
85: logger.info("Disconnecting the idle.");
86: // disconnect an idle client
87: session.close();
88: }
89:
90: @Override
91: public void exceptionCaught(IoSession session, Throwable cause) {
92: // close the connection on exceptional situation
93: session.close();
94: }
95: }
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