1 /***
2 *
3 * Copyright 2004 Protique Ltd
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 **/
18 package org.codehaus.activemq.transport.udp;
19
20 import EDU.oswego.cs.dl.util.concurrent.SynchronizedBoolean;
21 import org.apache.commons.logging.Log;
22 import org.apache.commons.logging.LogFactory;
23 import org.codehaus.activemq.message.Packet;
24 import org.codehaus.activemq.message.WireFormat;
25 import org.codehaus.activemq.transport.AbstractTransportChannel;
26 import org.codehaus.activemq.util.IdGenerator;
27
28 import javax.jms.JMSException;
29 import java.io.IOException;
30 import java.net.DatagramPacket;
31 import java.net.DatagramSocket;
32 import java.net.InetAddress;
33 import java.net.SocketTimeoutException;
34 import java.net.URI;
35
36 /***
37 * A UDP implementation of a TransportChannel
38 *
39 * @version $Revision: 1.19 $
40 */
41 public class UdpTransportChannel extends AbstractTransportChannel implements Runnable {
42
43 private static final int SOCKET_BUFFER_SIZE = 32 * 1024;
44 private static final int SO_TIMEOUT = 5000;
45 private static final Log log = LogFactory.getLog(UdpTransportChannel.class);
46
47 protected DatagramSocket socket;
48 protected int port;
49 protected InetAddress inetAddress;
50
51 private WireFormat wireFormat;
52 private SynchronizedBoolean closed;
53 private SynchronizedBoolean started;
54 private Thread thread;
55 private IdGenerator idGenerator = new IdGenerator();
56 private Object lock;
57
58
59 /***
60 * Construct basic helpers
61 */
62 protected UdpTransportChannel(WireFormat wireFormat) {
63 this.wireFormat = wireFormat;
64 closed = new SynchronizedBoolean(false);
65 started = new SynchronizedBoolean(false);
66 lock = new Object();
67 }
68
69 public UdpTransportChannel(WireFormat wireFormat, URI remoteLocation) throws JMSException {
70 this(wireFormat, remoteLocation, remoteLocation.getPort());
71 }
72
73 public UdpTransportChannel(WireFormat wireFormat, URI remoteLocation, int port) throws JMSException {
74 this(wireFormat);
75 try {
76 this.port = port;
77 this.inetAddress = InetAddress.getByName(remoteLocation.getHost());
78 this.socket = createSocket(remoteLocation.getPort());
79
80
81
82
83 socket.setReceiveBufferSize(SOCKET_BUFFER_SIZE);
84 socket.setSendBufferSize(SOCKET_BUFFER_SIZE);
85
86 connect();
87
88
89 }
90 catch (Exception ioe) {
91 JMSException jmsEx = new JMSException("Initialization of TransportChannel failed: " + ioe);
92 jmsEx.setLinkedException(ioe);
93 throw jmsEx;
94 }
95 }
96
97 /***
98 * @param socket
99 * @throws JMSException
100 */
101 public UdpTransportChannel(WireFormat wireFormat, DatagramSocket socket) throws JMSException {
102 this(wireFormat);
103 this.socket = socket;
104 this.port = socket.getPort();
105 this.inetAddress = socket.getInetAddress();
106 try {
107 socket.setReceiveBufferSize(SOCKET_BUFFER_SIZE);
108 socket.setSendBufferSize(SOCKET_BUFFER_SIZE);
109 }
110 catch (IOException ioe) {
111 JMSException jmsEx = new JMSException("Initialization of TransportChannel failed");
112 jmsEx.setLinkedException(ioe);
113 throw jmsEx;
114 }
115 }
116
117 public UdpTransportChannel(WireFormat wireFormat, DatagramSocket socket, int port) throws JMSException {
118 this(wireFormat, socket);
119 this.port = port;
120 }
121
122 /***
123 * close the channel
124 */
125 public void stop() {
126 if (closed.commit(false, true)) {
127 super.stop();
128 try {
129 socket.close();
130 }
131 catch (Exception e) {
132 log.trace(toString() + " now closed");
133 }
134 }
135 }
136
137 /***
138 * start listeneing for events
139 *
140 * @throws JMSException if an error occurs
141 */
142 public void start() throws JMSException {
143 if (started.commit(false, true)) {
144 thread = new Thread(this, "Thread:" + toString());
145 thread.setDaemon(true);
146 thread.start();
147 }
148 }
149
150
151 /***
152 * Asynchronously send a Packet
153 *
154 * @param packet
155 * @throws JMSException
156 */
157 public void asyncSend(Packet packet) throws JMSException {
158 try {
159 if (log.isDebugEnabled()) {
160 log.debug("Sending packet: " + packet);
161 }
162 DatagramPacket dpacket = createDatagramPacket(packet);
163
164
165
166
167 socket.send(dpacket);
168
169 }
170 catch (IOException e) {
171 JMSException jmsEx = new JMSException("asyncSend failed " + e);
172 jmsEx.setLinkedException(e);
173 throw jmsEx;
174 }
175 }
176
177 public boolean isMulticast() {
178 return false;
179 }
180
181 /***
182 * reads packets from a Socket
183 */
184 public void run() {
185 while (!closed.get()) {
186 try {
187 socket.setSoTimeout(SO_TIMEOUT);
188
189 DatagramPacket dpacket = createDatagramPacket();
190 while (!socket.isClosed()) {
191 socket.setSoTimeout(0);
192 socket.receive(dpacket);
193 Packet packet = wireFormat.readPacket(getClientID(), dpacket);
194 if (packet != null) {
195 doConsumePacket(packet);
196 }
197 }
198
199 log.trace("The socket peer is now closed");
200 doClose(new IOException("Socket peer is now closed"));
201 }
202 catch (SocketTimeoutException ste) {
203
204 }
205 catch (IOException e) {
206 doClose(e);
207 }
208 }
209 }
210
211 /***
212 * @return
213 */
214 protected DatagramPacket createDatagramPacket() {
215 DatagramPacket answer = new DatagramPacket(new byte[SOCKET_BUFFER_SIZE], SOCKET_BUFFER_SIZE);
216 if (port >= 0) {
217 answer.setPort(port);
218 }
219 answer.setAddress(inetAddress);
220 return answer;
221 }
222
223 protected DatagramPacket createDatagramPacket(Packet packet) throws IOException, JMSException {
224
225
226
227
228 DatagramPacket answer = wireFormat.writePacket(getClientID(), packet);
229 if (port >= 0) {
230 answer.setPort(port);
231 }
232 answer.setAddress(inetAddress);
233 return answer;
234 }
235
236 private void doClose(Exception ex) {
237 if (!closed.get()) {
238 JMSException jmsEx = new JMSException("Error reading socket: " + ex.getMessage());
239 jmsEx.setLinkedException(ex);
240 onAsyncException(jmsEx);
241 stop();
242 }
243 }
244
245 protected void connect() throws IOException {
246
247 }
248
249 protected DatagramSocket createSocket(int port) throws IOException {
250 return new DatagramSocket(port, inetAddress);
251 }
252
253 /***
254 * pretty print for object
255 *
256 * @return String representation of this object
257 */
258 public String toString() {
259 return "UdpTransportChannel: " + socket;
260 }
261 }