1 /***
2 *
3 * Copyright 2004 Hiram Chirino
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.activeio.filter;
18
19 import java.io.IOException;
20
21 import org.activeio.AsynchChannel;
22 import org.activeio.FilterAsynchChannel;
23 import org.activeio.Packet;
24
25 /***
26 * This PacketAggregatingAsynchChannel can be used when the client is sending a
27 * 'record' style packet down the channel stack and needs receiving end to
28 * receive the same 'record' packets.
29 *
30 * This is very usefull since in general, a channel does not garantee that a
31 * Packet that is sent down will not be fragmented or combined with other Packet
32 * objects.
33 *
34 * This {@see org.activeio.AsynchChannel} adds a 4 byte header
35 * to each packet that is sent down.
36 *
37 * @version $Revision$
38 */
39 final public class PacketAggregatingAsynchChannel extends FilterAsynchChannel {
40
41 private final PacketAggregator aggregator = new PacketAggregator() {
42 protected void packetAssembled(Packet packet) {
43 getAsynchChannelListener().onPacket(packet);
44 }
45 };
46
47 public PacketAggregatingAsynchChannel(AsynchChannel next) {
48 super(next);
49 }
50
51 public void onPacket(Packet packet) {
52 try {
53 aggregator.addRawPacket(packet);
54 } catch (IOException e) {
55 getAsynchChannelListener().onPacketError(e);
56 }
57 }
58
59 public void write(Packet packet) throws IOException {
60 getNext().write(aggregator.getHeader(packet));
61 getNext().write(packet);
62 }
63
64 }