/*
* Copyright 2011 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package io.netty.example.qotm;
import java.net.InetSocketAddress;
import java.util.concurrent.Executors;
import io.netty.bootstrap.ConnectionlessBootstrap;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.ChannelPipelineFactory;
import io.netty.channel.Channels;
import io.netty.channel.FixedReceiveBufferSizePredictorFactory;
import io.netty.channel.socket.DatagramChannel;
import io.netty.channel.socket.DatagramChannelFactory;
import io.netty.channel.socket.nio.NioDatagramChannelFactory;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.codec.string.StringEncoder;
import io.netty.util.CharsetUtil;
/**
* A UDP broadcast client that asks for a quote of the moment (QOTM) to
* {@link QuoteOfTheMomentServer}.
*
* Inspired by <a href="http://java.sun.com/docs/books/tutorial/networking/datagrams/clientServer.html">the official Java tutorial</a>.
*/
public class QuoteOfTheMomentClient {
private final int port;
public QuoteOfTheMomentClient(int port) {
this.port = port;
}
public void run() {
DatagramChannelFactory f =
new NioDatagramChannelFactory(Executors.newCachedThreadPool());
ConnectionlessBootstrap b = new ConnectionlessBootstrap(f);
// Configure the pipeline factory.
b.setPipelineFactory(new ChannelPipelineFactory() {
public ChannelPipeline getPipeline() throws Exception {
return Channels.pipeline(
new StringEncoder(CharsetUtil.ISO_8859_1),
new StringDecoder(CharsetUtil.ISO_8859_1),
new QuoteOfTheMomentClientHandler());
}
});
// Enable broadcast
b.setOption("broadcast", "true");
// Allow packets as large as up to 1024 bytes (default is 768).
// You could increase or decrease this value to avoid truncated packets
// or to improve memory footprint respectively.
//
// Please also note that a large UDP packet might be truncated or
// dropped by your router no matter how you configured this option.
// In UDP, a packet is truncated or dropped if it is larger than a
// certain size, depending on router configuration. IPv4 routers
// truncate and IPv6 routers drop a large packet. That's why it is
// safe to send small packets in UDP.
b.setOption(
"receiveBufferSizePredictorFactory",
new FixedReceiveBufferSizePredictorFactory(1024));
DatagramChannel c = (DatagramChannel) b.bind(new InetSocketAddress(0));
// Broadcast the QOTM request to port 8080.
c.write("QOTM?", new InetSocketAddress("255.255.255.255", port));
// QuoteOfTheMomentClientHandler will close the DatagramChannel when a
// response is received. If the channel is not closed within 5 seconds,
// print an error message and quit.
if (!c.getCloseFuture().awaitUninterruptibly(5000)) {
System.err.println("QOTM request timed out.");
c.close().awaitUninterruptibly();
}
f.releaseExternalResources();
}
public static void main(String[] args) throws Exception {
int port;
if (args.length > 0) {
port = Integer.parseInt(args[0]);
} else {
port = 8080;
}
new QuoteOfTheMomentClient(port).run();
}
}