serversessionhandler.java

MINA自带的一些小例子

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 *  to you under the Apache License, Version 2.0 (the
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package org.apache.mina.example.sumup;

import org.apache.mina.common.IdleStatus;
import org.apache.mina.common.IoHandler;
import org.apache.mina.common.IoHandlerAdapter;
import org.apache.mina.common.IoSession;
import org.apache.mina.example.sumup.message.AddMessage;
import org.apache.mina.example.sumup.message.ResultMessage;
import org.apache.mina.util.SessionLog;

/**
 * {@link IoHandler} for SumUp server.
 * 
 * @author The Apache Directory Project ([e-mail])
 * @version $Rev: 555855 $, $Date: 2007-07-13 12:19:00 +0900 (금, 13  7월 2007) $
 */
public class ServerSessionHandler extends IoHandlerAdapter {
    public void sessionOpened(IoSession session) {
        // set idle time to 60 seconds
        session.setIdleTime(IdleStatus.BOTH_IDLE, 60);

        // initial sum is zero
        session.setAttachment(new Integer(0));
    }

    public void messageReceived(IoSession session, Object message) {
        // client only sends AddMessage. otherwise, we will have to identify
        // its type using instanceof operator.
        AddMessage am = (AddMessage) message;

        // add the value to the current sum.
        int sum = ((Integer) session.getAttachment()).intValue();
        int value = am.getValue();
        long expectedSum = (long) sum + value;
        if (expectedSum > Integer.MAX_VALUE || expectedSum < Integer.MIN_VALUE) {
            // if the sum overflows or underflows, return error message
            ResultMessage rm = new ResultMessage();
            rm.setSequence(am.getSequence()); // copy sequence
            rm.setOk(false);
            session.write(rm);
        } else {
            // sum up
            sum = (int) expectedSum;
            session.setAttachment(new Integer(sum));

            // return the result message
            ResultMessage rm = new ResultMessage();
            rm.setSequence(am.getSequence()); // copy sequence
            rm.setOk(true);
            rm.setValue(sum);
            session.write(rm);
        }
    }

    public void sessionIdle(IoSession session, IdleStatus status) {
        SessionLog.info(session, "Disconnecting the idle.");
        // disconnect an idle client
        session.close();
    }

    public void exceptionCaught(IoSession session, Throwable cause) {
        // close the connection on exceptional situation
        session.close();
    }
}