org.apache.mina.core.service.IoHandler Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
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package org.apache.mina.core.service;
import java.io.IOException;
import org.apache.mina.core.session.IdleStatus;
import org.apache.mina.core.session.IoSession;
import org.apache.mina.filter.FilterEvent;
/**
* Handles all I/O events fired by MINA.
*
* @author Apache MINA Project
*
* @see IoHandlerAdapter
*/
public interface IoHandler {
/**
* Invoked from an I/O processor thread when a new connection has been created.
* Because this method is supposed to be called from the same thread that
* handles I/O of multiple sessions, please implement this method to perform
* tasks that consumes minimal amount of time such as socket parameter
* and user-defined session attribute initialization.
*
* @param session The session being created
* @throws Exception If we get an exception while processing the create event
*/
void sessionCreated(IoSession session) throws Exception;
/**
* Invoked when a connection has been opened. This method is invoked after
* {@link #sessionCreated(IoSession)}. The biggest difference from
* {@link #sessionCreated(IoSession)} is that it's invoked from other thread
* than an I/O processor thread once thread model is configured properly.
*
* @param session The session being opened
* @throws Exception If we get an exception while processing the open event
*/
void sessionOpened(IoSession session) throws Exception;
/**
* Invoked when a connection is closed.
*
* @param session The session being closed
* @throws Exception If we get an exception while processing the close event
*/
void sessionClosed(IoSession session) throws Exception;
/**
* Invoked with the related {@link IdleStatus} when a connection becomes idle.
* This method is not invoked if the transport type is UDP; it's a known bug,
* and will be fixed in 2.0.
*
* @param session The idling session
* @param status The session's status
* @throws Exception If we get an exception while processing the idle event
*/
void sessionIdle(IoSession session, IdleStatus status) throws Exception;
/**
* Invoked when any exception is thrown by user {@link IoHandler}
* implementation or by MINA. If cause is an instance of
* {@link IOException}, MINA will close the connection automatically.
*
* @param session The session for which we have got an exception
* @param cause The exception that has been caught
* @throws Exception If we get an exception while processing the caught exception
*/
void exceptionCaught(IoSession session, Throwable cause) throws Exception;
/**
* Invoked when a message is received.
*
* @param session The session that is receiving a message
* @param message The received message
* @throws Exception If we get an exception while processing the received message
*/
void messageReceived(IoSession session, Object message) throws Exception;
/**
* Invoked when a message written by {@link IoSession#write(Object)} is
* sent out.
*
* @param session The session that has sent a full message
* @param message The sent message
* @throws Exception If we get an exception while processing the sent message
*/
void messageSent(IoSession session, Object message) throws Exception;
/**
* Handle the closure of an half-duplex TCP channel
*
* @param session The session which input is being closed
* @throws Exception If we get an exception while closing the input
*/
void inputClosed(IoSession session) throws Exception;
/**
* Invoked when a filter event is fired. Each filter might sent a different event,
* this is very application specific.
*
* @param session The session for which we have an event to process
* @param event The event to process
* @throws Exception If we get an exception while processing the event
*/
void event(IoSession session, FilterEvent event) throws Exception;
}