1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.mina.common;
21
22 import java.io.IOException;
23
24 /**
25 * Handles all I/O events fired by MINA.
26 *
27 * @author The Apache MINA Project (dev@mina.apache.org)
28 * @version $Rev: 562343 $, $Date: 2007-08-03 14:53:44 +0900 (Fri, 03 Aug 2007) $
29 *
30 * @see IoHandlerAdapter
31 */
32 public interface IoHandler {
33 /**
34 * Invoked from an I/O processor thread when a new connection has been created.
35 * Because this method is supposed to be called from the same thread that
36 * handles I/O of multiple sessions, please implement this method to perform
37 * tasks that consumes minimal amount of time such as socket parameter
38 * and user-defined session attribute initialization.
39 */
40 void sessionCreated(IoSession session) throws Exception;
41
42 /**
43 * Invoked when a connection has been opened. This method is invoked after
44 * {@link #sessionCreated(IoSession)}. The biggest difference from
45 * {@link #sessionCreated(IoSession)} is that it's invoked from other thread
46 * than an I/O processor thread once thread modesl is configured properly.
47 */
48 void sessionOpened(IoSession session) throws Exception;
49
50 /**
51 * Invoked when a connection is closed.
52 */
53 void sessionClosed(IoSession session) throws Exception;
54
55 /**
56 * Invoked with the related {@link IdleStatus} when a connection becomes idle.
57 * This method is not invoked if the transport type is UDP; it's a known bug,
58 * and will be fixed in 2.0.
59 */
60 void sessionIdle(IoSession session, IdleStatus status) throws Exception;
61
62 /**
63 * Invoked when any exception is thrown by user {@link IoHandler}
64 * implementation or by MINA. If <code>cause</code> is instanceof
65 * {@link IOException}, MINA will close the connection automatically.
66 */
67 void exceptionCaught(IoSession session, Throwable cause) throws Exception;
68
69 /**
70 * Invoked when a message is received.
71 */
72 void messageReceived(IoSession session, Object message) throws Exception;
73
74 /**
75 * Invoked when a message written by {@link IoSession#write(Object)} is
76 * sent out.
77 */
78 void messageSent(IoSession session, Object message) throws Exception;
79 }