keepalivemessagefactory.java

mina是以Java实现的一个开源的网络程序框架

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 *  Licensed to the Apache Software Foundation (ASF) under one
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 *  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
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package org.apache.mina.filter.keepalive;

import org.apache.mina.core.session.IoSession;

/**
 * Provides keep-alive messages to {@link KeepAliveFilter}.
 *  
 * @author The Apache MINA Project ([e-mail])
 * @version $Rev: 671827 $, $Date: 2008-06-26 10:49:48 +0200 (Thu, 26 Jun 2008) $
 */
public interface KeepAliveMessageFactory {
    
    /**
     * Returns <tt>true</tt> if and only if the specified message is a
     * keep-alive request message.
     */
    boolean isRequest(IoSession session, Object message);

    /**
     * Returns <tt>true</tt> if and only if the specified message is a 
     * keep-alive response message;
     */
    boolean isResponse(IoSession session, Object message);
    
    /**
     * Returns a (new) keep-alive request message.
     * Returns <tt>null</tt> if no request is required.
     */
    Object getRequest(IoSession session);
    
    /**
     * Returns a (new) response message for the specified keep-alive request.
     * Returns <tt>null</tt> if no response is required.
     */
    Object getResponse(IoSession session, Object request);
}