1 /*
2 * Copyright 2012 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package org.jboss.netty.example.qotm;
17
18 import java.net.InetSocketAddress;
19 import java.util.concurrent.Executors;
20
21 import org.jboss.netty.bootstrap.ConnectionlessBootstrap;
22 import org.jboss.netty.channel.ChannelPipeline;
23 import org.jboss.netty.channel.ChannelPipelineFactory;
24 import org.jboss.netty.channel.Channels;
25 import org.jboss.netty.channel.FixedReceiveBufferSizePredictorFactory;
26 import org.jboss.netty.channel.socket.DatagramChannel;
27 import org.jboss.netty.channel.socket.DatagramChannelFactory;
28 import org.jboss.netty.channel.socket.nio.NioDatagramChannelFactory;
29 import org.jboss.netty.handler.codec.string.StringDecoder;
30 import org.jboss.netty.handler.codec.string.StringEncoder;
31 import org.jboss.netty.util.CharsetUtil;
32
33 /**
34 * A UDP broadcast client that asks for a quote of the moment (QOTM) to
35 * {@link QuoteOfTheMomentServer}.
36 *
37 * Inspired by <a href="http://goo.gl/BsXVR">the official Java tutorial</a>.
38 */
39 public class QuoteOfTheMomentClient {
40
41 private final int port;
42
43 public QuoteOfTheMomentClient(int port) {
44 this.port = port;
45 }
46
47 public void run() {
48 DatagramChannelFactory f =
49 new NioDatagramChannelFactory(Executors.newCachedThreadPool());
50
51 ConnectionlessBootstrap b = new ConnectionlessBootstrap(f);
52
53 // Configure the pipeline factory.
54 b.setPipelineFactory(new ChannelPipelineFactory() {
55 public ChannelPipeline getPipeline() throws Exception {
56 return Channels.pipeline(
57 new StringEncoder(CharsetUtil.ISO_8859_1),
58 new StringDecoder(CharsetUtil.ISO_8859_1),
59 new QuoteOfTheMomentClientHandler());
60 }
61 });
62
63 // Enable broadcast
64 b.setOption("broadcast", "true");
65
66 // Allow packets as large as up to 1024 bytes (default is 768).
67 // You could increase or decrease this value to avoid truncated packets
68 // or to improve memory footprint respectively.
69 //
70 // Please also note that a large UDP packet might be truncated or
71 // dropped by your router no matter how you configured this option.
72 // In UDP, a packet is truncated or dropped if it is larger than a
73 // certain size, depending on router configuration. IPv4 routers
74 // truncate and IPv6 routers drop a large packet. That's why it is
75 // safe to send small packets in UDP.
76 b.setOption(
77 "receiveBufferSizePredictorFactory",
78 new FixedReceiveBufferSizePredictorFactory(1024));
79
80 DatagramChannel c = (DatagramChannel) b.bind(new InetSocketAddress(0));
81
82 // Broadcast the QOTM request to port 8080.
83 c.write("QOTM?", new InetSocketAddress("255.255.255.255", port));
84
85 // QuoteOfTheMomentClientHandler will close the DatagramChannel when a
86 // response is received. If the channel is not closed within 5 seconds,
87 // print an error message and quit.
88 if (!c.getCloseFuture().awaitUninterruptibly(5000)) {
89 System.err.println("QOTM request timed out.");
90 c.close().awaitUninterruptibly();
91 }
92
93 f.releaseExternalResources();
94 }
95
96 public static void main(String[] args) throws Exception {
97 int port;
98 if (args.length > 0) {
99 port = Integer.parseInt(args[0]);
100 } else {
101 port = 8080;
102 }
103 new QuoteOfTheMomentClient(port).run();
104 }
105 }