Netty學(xué)習(xí)教程之基礎(chǔ)使用篇

import io.netty.bootstrap.ServerBootstrap; 
import io.netty.buffer.ByteBuf; 
import io.netty.buffer.Unpooled; 
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; 
import io.netty.handler.codec.DelimiterBasedFrameDecoder; 
import io.netty.handler.codec.string.StringDecoder; 
 
public class Server { 
  
 public static void main(String[] args) throws InterruptedException { 
  //1.第一個(gè)線程組是用于接收Client端連接的 
  EventLoopGroup bossGroup = new NioEventLoopGroup(); 
  //2.第二個(gè)線程組是用于實(shí)際的業(yè)務(wù)處理的 
  EventLoopGroup workerGroup = new NioEventLoopGroup(); 
  ServerBootstrap b = new ServerBootstrap(); 
  b.group(bossGroup, workerGroup);//綁定兩個(gè)線程池 
  b.channel(NioServerSocketChannel.class);//指定NIO的模式，如果是客戶端就是NioSocketChannel 
  b.option(ChannelOption.SO_BACKLOG, 1024);//TCP的緩沖區(qū)設(shè)置 
  b.option(ChannelOption.SO_SNDBUF, 32*1024);//設(shè)置發(fā)送緩沖的大小 
  b.option(ChannelOption.SO_RCVBUF, 32*1024);//設(shè)置接收緩沖區(qū)大小 
  b.option(ChannelOption.SO_KEEPALIVE, true);//保持連續(xù) 
  b.childHandler(new ChannelInitializer<SocketChannel>() { 
   @Override 
   protected void initChannel(SocketChannel sc) throws Exception { 
    ByteBuf buf = Unpooled.copiedBuffer("$_".getBytes());//拆包粘包定義結(jié)束字符串（第一種解決方案） 
    sc.pipeline().addLast(new DelimiterBasedFrameDecoder(1024,buf));//在管道中加入結(jié)束字符串 
   // sc.pipeline().addLast(new FixedLengthFrameDecoder(200));第二種定長(zhǎng) 
    sc.pipeline().addLast(new StringDecoder());//定義接收類型為字符串把ByteBuf轉(zhuǎn)成String 
    sc.pipeline().addLast(new ServertHandler());//在這里配置具體數(shù)據(jù)接收方法的處理 
   } 
  }); 
  ChannelFuture future = b.bind(8765).sync();//綁定端口 
  future.channel().closeFuture().sync();//等待關(guān)閉(程序阻塞在這里等待客戶端請(qǐng)求) 
  bossGroup.shutdownGracefully();//關(guān)閉線程 
  workerGroup.shutdownGracefully();//關(guān)閉線程 
 } 
} 

public class ServertHandler extends ChannelHandlerAdapter { 
 
 @Override 
 public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { 
  String body = (String) msg; 
  System.out.println("server"+body);//前面已經(jīng)定義了接收為字符串，這里直接接收字符串就可以 
  //服務(wù)端給客戶端的響應(yīng) 
  String response= " hi client!$_";//發(fā)送的數(shù)據(jù)以定義結(jié)束的字符串結(jié)尾 
  ctx.writeAndFlush(Unpooled.copiedBuffer(response.getBytes()));//發(fā)送必須還是ByteBuf類型 
 } 
 
 @Override 
 public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { 
   cause.printStackTrace(); 
   ctx.close(); 
 } 
  
} 

public class Client { 
 
 public static void main(String[] args) throws InterruptedException { 
  EventLoopGroup worker = new NioEventLoopGroup(); 
  Bootstrap b = new Bootstrap(); 
  b.group(worker) 
  .channel(NioSocketChannel.class) 
  .handler(new ChannelInitializer<SocketChannel>() { 
   @Override 
   protected void initChannel(SocketChannel sc) throws Exception { 
    ByteBuf buf = Unpooled.copiedBuffer("$_".getBytes()); 
    sc.pipeline().addLast(new DelimiterBasedFrameDecoder(1024,buf)); 
    sc.pipeline().addLast(new StringDecoder()); 
    sc.pipeline().addLast(new ClientHandler()); 
   } 
  }); 
  ChannelFuture f=b.connect("127.0.0.1",8765).sync(); 
  f.channel().writeAndFlush(Unpooled.copiedBuffer(" hi server2$_".getBytes())); 
  f.channel().writeAndFlush(Unpooled.copiedBuffer(" hi server3$_".getBytes())); 
  f.channel().writeAndFlush(Unpooled.copiedBuffer(" hi server4$_".getBytes())); 
  f.channel().closeFuture().sync(); 
  worker.shutdownGracefully(); 
 } 
} 

public class ClientHandler extends ChannelHandlerAdapter{ 
 @Override 
 public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception { 
  try { 
   System.out.println("client"+msg.toString()); 
  } finally { 
   ReferenceCountUtil.release(msg);//釋放緩沖區(qū) 
  } 
 } 
 
 @Override 
 public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { 
   cause.printStackTrace(); 
   ctx.close(); 
 } 
}