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
21 package org.apache.mina.api;
22
23 import org.apache.mina.filterchain.ReadFilterChainController;
24 import org.apache.mina.filterchain.WriteFilterChainController;
25 import org.apache.mina.session.WriteRequest;
26
27 /**
28 * Filter are interceptors/processors for incoming data received/sent.
29 *
30 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
31 */
32 public interface IoFilter {
33
34 /**
35 * Invoked when a connection has been opened.
36 *
37 * @param session {@link IoSession} associated with the invocation
38 */
39 void sessionOpened(IoSession session);
40
41 /**
42 * Invoked when a connection is closed.
43 *
44 * @param session {@link IoSession} associated with the invocation
45 */
46 void sessionClosed(IoSession session);
47
48 /**
49 * Invoked with the related {@link IdleStatus} when a connection becomes idle.
50 *
51 * @param session {@link IoSession} associated with the invocation
52 */
53 void sessionIdle(IoSession session, IdleStatus status);
54
55 /**
56 * Invoked when a message is received.
57 *
58 * @param session {@link IoSession} associated with the invocation
59 * @param message the incoming message to process
60 */
61 void messageReceived(IoSession session, Object message, ReadFilterChainController controller);
62
63 /**
64 * Invoked when a message is under writing. The filter is supposed to apply the needed transformation.
65 *
66 * @param session {@link IoSession} associated with the invocation
67 * @param message the message to process before writing
68 */
69 void messageWriting(IoSession session, WriteRequest message, WriteFilterChainController controller);
70
71 /**
72 * Invoked when a high level message was written to the low level O/S buffer.
73 *
74 * @param session {@link IoSession} associated with the invocation
75 * @param message the incoming message to process
76 */
77 void messageSent(IoSession session, Object message);
78 }