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.filter.codec.demux;
21
22 import org.apache.mina.core.buffer.IoBuffer;
23 import org.apache.mina.core.session.IoSession;
24 import org.apache.mina.filter.codec.ProtocolEncoderOutput;
25
26 /**
27 * Encodes a certain type of messages.
28 * <p>
29 * We didn't provide any <tt>dispose</tt> method for {@link MessageEncoder}
30 * because it can give you performance penalty in case you have a lot of
31 * message types to handle.
32 *
33 * @author The Apache MINA Project (dev@mina.apache.org)
34 *
35 * @see DemuxingProtocolEncoder
36 * @see MessageEncoderFactory
37 */
38 public interface MessageEncoder<T> {
39 /**
40 * Encodes higher-level message objects into binary or protocol-specific data.
41 * MINA invokes {@link #encode(IoSession, Object, ProtocolEncoderOutput)}
42 * method with message which is popped from the session write queue, and then
43 * the encoder implementation puts encoded {@link IoBuffer}s into
44 * {@link ProtocolEncoderOutput}.
45 *
46 * @throws Exception if the message violated protocol specification
47 */
48 void encode(IoSession session, T message, ProtocolEncoderOutput out)
49 throws Exception;
50 }