Netty 入门demo

信息的发送与返回（这里有问题，但是没有发现问题在哪里，暂时存一下代码，后期深入研究的时候，再来补）

public class TimeClient {
	public void connect(int port,String host) throws InterruptedException {
		//配置客户端的nio线程组
		EventLoopGroup group=new NioEventLoopGroup();
		try {
			Bootstrap b=new Bootstrap();
			b.group(group).channel(NioSocketChannel.class)
			.option(ChannelOption.TCP_NODELAY, true)
			.handler(new ChannelInitializer<SocketChannel>() {
				public void initChannel(SocketChannel ch) throws Exception{
					 ch.pipeline().addLast(new TimeClientHandler());
				}
			});
			System.out.println("客户端启动成功，准备连接...");
			//发起异步连接操作。
			ChannelFuture f=b.connect(host,port).sync();
			System.out.print("连接成功\n");
			//等待客户端链路关闭
			f.channel().closeFuture().sync();
		}finally {
			group.shutdownGracefully();
		}
	}
	public static void main(String []args) throws InterruptedException {
		new TimeClient().connect(8888, "127.0.0.1");
	}
}

public class TimeClientHandler extends ChannelHandlerAdapter{
	private static final Logger logger=Logger.getLogger(TimeClientHandler.class.getName());
	private final ByteBuf firstMessage;
	public TimeClientHandler() {
		System.out.println("发送端 处理器 初始化...");
		byte[]req="query time order".getBytes();
		firstMessage=Unpooled.buffer(req.length);
		firstMessage.writeBytes(req);
	}
	//向服务器发送信息；
  public void channelActive(ChannelHandlerContext ctx) throws Exception {
		 System.out.println("发送消息");
	        ctx.write(firstMessage);
	        ctx.flush();
	    }
	 //接受服务器的信息
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        System.out.println("SimpleClientHandler.channelRead");
        ByteBuf result = (ByteBuf) msg;
        byte[] result1 = new byte[result.readableBytes()];
        result.readBytes(result1);
        System.out.println("Server said:" + new String(result1));
        result.release();
    }
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        // 当出现异常就关闭连接
        cause.printStackTrace();
        ctx.close();
    }
}

public class TimeServer {
	public void bind(int port) throws InterruptedException {
		//两个线程组，reactor线程组，一个负责接受，另外一个负责独写。
		EventLoopGroup bossGroup=new NioEventLoopGroup();
		EventLoopGroup workerGroup=new NioEventLoopGroup();
		//这里好像是注册，设置参数，绑定端口等等。
		ServerBootstrap b=new ServerBootstrap();  //它好像是一个辅助启动类。
		b.group(bossGroup,workerGroup)
		.channel(NioServerSocketChannel.class)
		.option(ChannelOption.SO_BACKLOG, 1024)
		.childHandler(new ChildChannelHandler());
		//绑定端口，同步等待成功。
		ChannelFuture f=b.bind(port).sync();
		
		System.out.print("等待客户端 连接...\n");
		//等待服务器端口监听关闭。
		f.channel().closeFuture().sync();
		//退出释放 资源
		bossGroup.shutdownGracefully();
		workerGroup.shutdownGracefully();
	}
	private class ChildChannelHandler extends ChannelInitializer<SocketChannel>{

		@Override
		protected void initChannel(SocketChannel arg0) throws Exception {
			arg0.pipeline().addLast(new TimeServerHandler());
		}
		
	}
	public static void main(String []args) {
		int port=8888;
		try {
			new TimeServer().bind(port);
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

public class TimeServerHandler extends ChannelHandlerAdapter {

	public void channeilRead(ChannelHandlerContext ctx,Object msg) throws UnsupportedEncodingException {
		ByteBuf buf=(ByteBuf) msg;  //缓冲，处理接受到的消息。
		byte[] req=new byte[buf.readableBytes()]; //转成byte类型吗？
		buf.readBytes(req); //将buf里面的内容，放到byte中。
		String body=new String(req,"UTF-8"); //又将字节组 转为字符串，编码方式设置。
		System.out.println("server 收到的内容："+body);
		
		String currentTime="query time order".equalsIgnoreCase(body)?new Date(
				System.currentTimeMillis()).toString():"bad order";
		ByteBuf resp=Unpooled.copiedBuffer(currentTime.getBytes());
		ctx.write(resp); //将时间转化成字节码，然后传入buffer，然后返回给客户端。
	}
	public void channelReadComplete(ChannelHandlerContext ctx) {
		ctx.flush();
	}
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        // 当出现异常就关闭连接
        cause.printStackTrace();
        ctx.close();
    }

}