messageencoder.java

mina是以Java实现的一个开源的网络程序框架

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package org.apache.mina.filter.codec.demux;

import org.apache.mina.core.buffer.IoBuffer;
import org.apache.mina.core.session.IoSession;
import org.apache.mina.filter.codec.ProtocolEncoderOutput;

/**
 * Encodes a certain type of messages.
 * <p>
 * We didn't provide any <tt>dispose</tt> method for {@link MessageEncoder}
 * because it can give you  performance penalty in case you have a lot of
 * message types to handle.
 * 
 * @author The Apache MINA Project ([e-mail])
 * @version $Rev: 671827 $, $Date: 2008-06-26 10:49:48 +0200 (Thu, 26 Jun 2008) $
 *
 * @see DemuxingProtocolEncoder
 * @see MessageEncoderFactory
 */
public interface MessageEncoder<T> {
    /**
     * Encodes higher-level message objects into binary or protocol-specific data.
     * MINA invokes {@link #encode(IoSession, Object, ProtocolEncoderOutput)}
     * method with message which is popped from the session write queue, and then
     * the encoder implementation puts encoded {@link IoBuffer}s into
     * {@link ProtocolEncoderOutput}.
     *
     * @throws Exception if the message violated protocol specification
     */
    void encode(IoSession session, T message, ProtocolEncoderOutput out)
            throws Exception;
}