View Javadoc

    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 05:19:00 +0200 (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  }