Source code: org/activemq/transport/activeio/PacketAggregator.java
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.activemq.transport.activeio;
18
19 import java.io.IOException;
20
21 import org.activeio.Packet;
22 import org.activeio.PacketData;
23 import org.activeio.packet.AppendedPacket;
24 import org.activeio.packet.EOSPacket;
25
26 /**
27 * @version $Revision: 1.1.1.1 $
28 */
29 abstract public class PacketAggregator {
30
31 private static final int HEADER_LENGTH = 5;
32
33 Packet incompleteUpPacket;
34 boolean headerLoaded;
35 private int upPacketLength;
36
37 public void addRawPacket(Packet packet) throws IOException {
38
39 // Passthrough the EOS packet.
40 if( packet == EOSPacket.EOS_PACKET ) {
41 packetAssembled(packet);
42 return;
43 }
44
45 if (incompleteUpPacket != null) {
46 packet = AppendedPacket.join(incompleteUpPacket, packet);
47 incompleteUpPacket = null;
48 }
49
50 while (true) {
51
52 if (!headerLoaded) {
53 headerLoaded = packet.remaining() >= HEADER_LENGTH;
54 if( headerLoaded ) {
55 PacketData data = new PacketData(packet.duplicate());
56 data.readByte();
57 upPacketLength = data.readInt();
58 if( upPacketLength < 0 ) {
59 throw new IOException("Up packet lenth was invalid: "+upPacketLength);
60 }
61 upPacketLength+=HEADER_LENGTH;
62 }
63 if( !headerLoaded )
64 break;
65 }
66
67 if (packet.remaining() < upPacketLength )
68 break;
69
70 // Get ready to create a slice to send up.
71 int origLimit = packet.limit();
72 packet.limit(upPacketLength);
73 packetAssembled(packet.slice());
74
75 // Get a slice of the remaining since that will dump
76 // the first packets of an AppendedPacket
77 packet.position(upPacketLength);
78 packet.limit(origLimit);
79 packet = packet.slice();
80
81 // Need to load a header again now.
82 headerLoaded = false;
83 }
84 if (packet.hasRemaining()) {
85 incompleteUpPacket = packet;
86 }
87
88 }
89
90 protected abstract void packetAssembled(Packet packet);
91 }