netty使用入门

package bhz.netty.helloworld;


import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;


public class ServerHandler extends ChannelHandlerAdapter {


@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
System.out.println("server channel active... ");
}


@Override
public void channelRead(ChannelHandlerContext ctx, Object msg)
throws Exception {
ByteBuf buf = (ByteBuf) msg;
byte[] req = new byte[buf.readableBytes()];
buf.readBytes(req);
String body = new String(req, "utf-8");
System.out.println("Server :" + body );
String response = "进行返回给客户端的响应：" + body ;
ctx.writeAndFlush(Unpooled.copiedBuffer(response.getBytes()));
//.addListener(ChannelFutureListener.CLOSE);
}


@Override
public void channelReadComplete(ChannelHandlerContext ctx)
throws Exception {
System.out.println("读完了");
ctx.flush();
}


@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable t)
throws Exception {
ctx.close();
}

}

package bhz.netty.helloworld;


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


public class Server {


public static void main(String[] args) throws Exception {
//1 创建线两个程组 
//一个是用于处理服务器端接收客户端连接的
//一个是进行网络通信的（网络读写的）
EventLoopGroup pGroup = new NioEventLoopGroup();
EventLoopGroup cGroup = new NioEventLoopGroup();

//2 创建辅助工具类，用于服务器通道的一系列配置
ServerBootstrap b = new ServerBootstrap();
b.group(pGroup, cGroup)//绑定俩个线程组
.channel(NioServerSocketChannel.class)//指定NIO的模式
.option(ChannelOption.SO_BACKLOG, 1024)//设置tcp缓冲区
.option(ChannelOption.SO_SNDBUF, 32*1024)//设置发送缓冲大小
.option(ChannelOption.SO_RCVBUF, 32*1024)//这是接收缓冲大小
.option(ChannelOption.SO_KEEPALIVE, true)//保持连接
.childHandler(new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel sc) throws Exception {
//3 在这里配置具体数据接收方法的处理
sc.pipeline().addLast(new ServerHandler());
}
});

//4 进行绑定 
ChannelFuture cf1 = b.bind(8765).sync();
//ChannelFuture cf2 = b.bind(8764).sync();
//5 等待关闭
cf1.channel().closeFuture().sync();
//cf2.channel().closeFuture().sync();
pGroup.shutdownGracefully();
cGroup.shutdownGracefully();
}
}

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPromise;
import io.netty.util.ReferenceCountUtil;


public class ClientHandler extends ChannelHandlerAdapter{


@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
}


@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
try {
ByteBuf buf = (ByteBuf) msg;

byte[] req = new byte[buf.readableBytes()];
buf.readBytes(req);

String body = new String(req, "utf-8");
System.out.println("Client :" + body );
String response = "收到服务器端的返回信息：" + body;
} finally {
ReferenceCountUtil.release(msg);
}
}

@Override
public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {


}

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


}

import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.Unpooled;
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.NioSocketChannel;


public class Client {


public static void main(String[] args) throws Exception{

EventLoopGroup group = new NioEventLoopGroup();
Bootstrap b = new Bootstrap();
b.group(group)
.channel(NioSocketChannel.class)
.handler(new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel sc) throws Exception {
sc.pipeline().addLast(new ClientHandler());
}
});

ChannelFuture cf1 = b.connect("127.0.0.1", 8765).sync();
//ChannelFuture cf2 = b.connect("127.0.0.1", 8764).sync();
//发送消息
Thread.sleep(1000);
cf1.channel().writeAndFlush(Unpooled.copiedBuffer("777".getBytes()));
cf1.channel().writeAndFlush(Unpooled.copiedBuffer("666".getBytes()));
//cf2.channel().writeAndFlush(Unpooled.copiedBuffer("888".getBytes()));
Thread.sleep(2000);
cf1.channel().writeAndFlush(Unpooled.copiedBuffer("888".getBytes()));
//cf2.channel().writeAndFlush(Unpooled.copiedBuffer("666".getBytes()));

cf1.channel().closeFuture().sync();
//cf2.channel().closeFuture().sync();
group.shutdownGracefully();

}
}