netty使用(2)创建一个EchoServer并且部署运行

1.打开Eclipse，File->New->Java Project，在弹出的对话框中，project name填写XXX，然后点击“finish”

2.右键该工程，new->Class，在弹出的对话框中，Package随便写一个club.test，Name写myhello

 3.下载netty，解压，选择all-in-one文件夹里面的final那个jar包。

4.把jar包添加到工程中去，

方法a：右键工程，new->Folder，命名为比如nettylib，复制netty的jar包，选中nettylib文件夹后，Ctrl+V粘帖。

右键，这个.jar包，Build path，Add to build path

方法b：右键工程，Build Path->Build Path Configurations,在弹出的对话框中，选中Libraries选项卡，点击Add External JAR

5. myhello.java文件代码如下

package club.test;


import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.util.CharsetUtil;

import java.net.InetSocketAddress;

/**
 * Listing 2.2 EchoServer class
 *
 * @author <a href="mailto:norman.maurer@gmail.com">Norman Maurer</a>
 */
public class myhello {
    private final int port;

    public myhello(int port) {
        this.port = port;
    }

    public static void main(String[] args)
        throws Exception {
        if (args.length != 0) {
            System.err.println("Usage: " + myhello.class.getSimpleName() +
                " <port>"
            );
            return;
        }
        //int port = Integer.parseInt(args[0]);
        new myhello(8888).start();
    }

    /**
     * @throws Exception
     */
    public void start() throws Exception {
        final goodHandler serverHandler = new goodHandler();
        EventLoopGroup group = new NioEventLoopGroup();
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(group)
                .channel(NioServerSocketChannel.class)
                .localAddress(new InetSocketAddress(port))
                .childHandler(new ChannelInitializer<SocketChannel>() {
                    @Override
                    public void initChannel(SocketChannel ch) throws Exception {
                        ch.pipeline().addLast(serverHandler);
                    }
                });

            ChannelFuture f = b.bind().sync();
            System.out.println(myhello.class.getName() +
                " started and listening for connections on " + f.channel().localAddress());
            f.channel().closeFuture().sync();
        } finally {
            group.shutdownGracefully().sync();
        }
    }
}
@Sharable
class goodHandler extends ChannelInboundHandlerAdapter {
    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) {
        ByteBuf in = (ByteBuf) msg;
        System.out.println(
                "Server received: " + in.toString(CharsetUtil.US_ASCII));
        ctx.write(in);
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx)
            throws Exception {
        ctx.writeAndFlush(Unpooled.EMPTY_BUFFER)
                .addListener(ChannelFutureListener.CLOSE);
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx,
        Throwable cause) {
        cause.printStackTrace();
        ctx.close();
    }
}

 如果需要参数，右键工程，run as ==》run configurations

在arguments，program arguments中输入

 6.导出可运行jar包

右键工程，export，在弹出对话框中选择java，ruannable JAR  file，

launch configuration对应本工程，目标文件夹选择好，其他默认。

 控制台中，到当前路径

java -jar XXX.jar

如果程序需要参数，直接加在最后。