io.netty.example.echo.EchoClient Maven / Gradle / Ivy
/*
* Copyright 2012 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.echo;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;
/**
* Sends one message when a connection is open and echoes back any received
* data to the server. Simply put, the echo client initiates the ping-pong
* traffic between the echo client and server by sending the first message to
* the server.
*/
public class EchoClient {
private final String host;
private final int port;
private final int firstMessageSize;
public EchoClient(String host, int port, int firstMessageSize) {
this.host = host;
this.port = port;
this.firstMessageSize = firstMessageSize;
}
public void run() throws Exception {
// Configure the client.
Bootstrap b = new Bootstrap();
try {
b.group(new NioEventLoopGroup())
.channel(NioSocketChannel.class)
.option(ChannelOption.TCP_NODELAY, true)
.handler(new ChannelInitializer() {
@Override
public void initChannel(SocketChannel ch) throws Exception {
ch.pipeline().addLast(
new LoggingHandler(LogLevel.INFO),
new EchoClientHandler(firstMessageSize));
}
});
// Start the client.
ChannelFuture f = b.connect(host, port).sync();
// Wait until the connection is closed.
f.channel().closeFuture().sync();
} finally {
// Shut down the event loop to terminate all threads.
b.shutdown();
}
}
public static void main(String[] args) throws Exception {
// Print usage if no argument is specified.
if (args.length < 2 || args.length > 3) {
System.err.println(
"Usage: " + EchoClient.class.getSimpleName() +
" []");
return;
}
// Parse options.
final String host = args[0];
final int port = Integer.parseInt(args[1]);
final int firstMessageSize;
if (args.length == 3) {
firstMessageSize = Integer.parseInt(args[2]);
} else {
firstMessageSize = 256;
}
new EchoClient(host, port, firstMessageSize).run();
}
}