reverseprotocolhandler.java

mina是以Java实现的一个开源的网络程序框架

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 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
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 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
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package org.apache.mina.example.reverser;

import org.apache.mina.core.service.IoHandler;
import org.apache.mina.core.service.IoHandlerAdapter;
import org.apache.mina.core.session.IoSession;

/**
 * {@link IoHandler} implementation of reverser server protocol.
 *
 * @author The Apache MINA Project ([e-mail])
 * @version $Rev: 713957 $, $Date: 2008-11-14 10:27:16 +0100 (Fri, 14 Nov 2008) $,
 */
public class ReverseProtocolHandler extends IoHandlerAdapter {
    @Override
    public void exceptionCaught(IoSession session, Throwable cause) {
        // Close connection when unexpected exception is caught.
        session.close(true);
    }

    @Override
    public void messageReceived(IoSession session, Object message) {
        // Reverse reveiced string
        String str = message.toString();
        StringBuilder buf = new StringBuilder(str.length());
        for (int i = str.length() - 1; i >= 0; i--) {
            buf.append(str.charAt(i));
        }

        // and write it back.
        session.write(buf.toString());
    }
}