Netty入门实例及分析

import java.net.InetSocketAddress;
import java.util.concurrent.Executors;

import org.jboss.netty.bootstrap.ClientBootstrap;
import org.jboss.netty.channel.ChannelFactory;
import org.jboss.netty.channel.ChannelPipeline;
import org.jboss.netty.channel.ChannelPipelineFactory;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.socket.nio.NioClientSocketChannelFactory;

public class TimeClient {
	public static void main(String[] args) {
		String host = args[0];
		int port = Integer.parseInt(args[1]);
		
		ChannelFactory factory = new NioClientSocketChannelFactory(
				Executors.newCachedThreadPool(), Executors.newCachedThreadPool());
		ClientBootstrap bootstrap = new ClientBootstrap(factory);
		bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
			@Override
			public ChannelPipeline getPipeline() throws Exception {
				return Channels.pipeline(new TimeClientHandler2());
			}
		});
		bootstrap.connect(new InetSocketAddress(host, port));  //
	}

}

import java.util.Date;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelHandler;

public class TimeClientHandler extends SimpleChannelHandler{
	@Override
	public void messageReceived(ChannelHandlerContext ctx, MessageEvent e)
			throws Exception {
		ChannelBuffer buffer = (ChannelBuffer)e.getMessage();
		long currentTimeMills = buffer.readInt() * 1000L;
		System.out.println(new Date(currentTimeMills));
		e.getChannel().close();
	}
	
	@Override
	public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
			throws Exception {
		e.getCause().printStackTrace();
		Channel c = e.getChannel();
		c.close();
	}
}

import java.net.InetSocketAddress;
import java.util.concurrent.Executors;

import org.jboss.netty.bootstrap.ServerBootstrap;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFactory;
import org.jboss.netty.channel.ChannelPipeline;
import org.jboss.netty.channel.ChannelPipelineFactory;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.group.ChannelGroup;
import org.jboss.netty.channel.group.ChannelGroupFuture;
import org.jboss.netty.channel.group.DefaultChannelGroup;
import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory;

public class TimeServer {
	public static ChannelGroup allChannels = new DefaultChannelGroup("time-server");
	
	public static void main(String[] args) {
		ChannelFactory factory = new NioServerSocketChannelFactory(
				Executors.newCachedThreadPool(),
				Executors.newCachedThreadPool());
		
		ServerBootstrap bootstrap = new ServerBootstrap(factory);
		bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
			@Override
			public ChannelPipeline getPipeline() throws Exception {
				return Channels.pipeline(new TimeServerHandler2(),
										 new TimeEncoder());
			}
		});
		
		bootstrap.setOption("reuseAddr", true);
		bootstrap.setOption("child.tcpNoDelay", true);
		bootstrap.setOption("child.keepAlive", true);
		
		Channel channel = bootstrap.bind(new InetSocketAddress(8080));
		
		allChannels.add(channel);
		//waitForShutdownCommand();  this is a imaginary logic:for instance 
		//when there is accepted connection we close this server ;
		if(allChannels.size() >=2){
			ChannelGroupFuture f = allChannels.close();
			f.awaitUninterruptibly();
			factory.releaseExternalResources();
		}
	}
}

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ChannelStateEvent;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.SimpleChannelHandler;

public class TimeServerHandler extends SimpleChannelHandler{
	@Override
	public void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e)
			throws Exception {
		Channel ch = e.getChannel();
		ChannelBuffer time = ChannelBuffers.buffer(4); //sizeof int
		time.writeInt((int)(System.currentTimeMillis()/1000L + 2208988800L));
		
		ChannelFuture cf = ch.write(time);
		cf.addListener(new ChannelFutureListener() {
			@Override
			public void operationComplete(ChannelFuture future) throws Exception {
				Channel ch = future.getChannel();
				ch.close();
			}
		});
	}
	@Override
	public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e)
			throws Exception {
		e.getCause().printStackTrace();
		Channel c = e.getChannel();
		c.close();
	}
}