Netty的socket編程(四)

標籤：put   bootstrap   net   handle   active   final   tin   rup   write   

Netty提供的handler：編解碼，訊息頭，訊息編碼

 

1. 串連建立後，用戶端和服務端都不會主動發訊息，實現handler的channelActive來觸發訊息發送。

2.SimpleChannelInboundHandler的重載方法

(1)handlerAdded  串連建立時調用

(2)HandlerRemoved 串連斷開時調用

(3)HandlerActive 串連處於活動狀態調用

(4)HandlerInactive 串連處於不活動狀態調用

 

socket樣本 ：

server啟動類：

 

 1 public class MyServer { 2  3     public static void main(String[] args) throws InterruptedException { 4  5         EventLoopGroup bossGroup = new NioEventLoopGroup(); 6         EventLoopGroup workerGroup = new NioEventLoopGroup(); 7  8         try{ 9             ServerBootstrap serverBootstrap = new ServerBootstrap();10             serverBootstrap.group(bossGroup,workerGroup).11                     channel(NioServerSocketChannel.class)12                     .childHandler(new MyServerInitializer());13             ChannelFuture channelFuture = serverBootstrap.bind(8899).sync();14             channelFuture.channel().closeFuture().sync();15 16         }finally {17 18             bossGroup.shutdownGracefully();19             workerGroup.shutdownGracefully();20 21         }22 23     }24 25 }

 

 

server初始化類 ：

 1 public class MyServerInitializer  extends ChannelInitializer<SocketChannel>{ 2  3  4     @Override 5     protected void initChannel(SocketChannel ch) throws Exception { 6  7         ChannelPipeline channelPipeline = ch.pipeline(); 8  9         //解碼器10         channelPipeline.addLast(new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE,0,4,0,4));11         //訊息 加header12         channelPipeline.addLast(new LengthFieldPrepender(4));13         channelPipeline.addLast(new StringDecoder(CharsetUtil.UTF_8));14         channelPipeline.addLast(new StringEncoder(CharsetUtil.UTF_8));15         channelPipeline.addLast(new MyServerHandler());16 17     }18 }

 

server業務處理handler：

 1 public class MyServerHandler extends SimpleChannelInboundHandler<String> { 2     @Override 3     protected void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception { 4  5         System.out.println(ctx.channel().remoteAddress()+"msg:"+msg); 6  7         ctx.channel().writeAndFlush("from server "+ UUID.randomUUID()); 8  9     }10 11     @Override12     public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {13         cause.printStackTrace();14         ctx.close();15     }16 }

 

 

client 類：

client啟動類：

 1 public class MyClient { 2  3     public static void main(String[] args) throws InterruptedException { 4  5         EventLoopGroup eventLoopGroup = new NioEventLoopGroup(); 6  7         try{ 8             Bootstrap bootstrap = new Bootstrap(); 9             bootstrap.group(eventLoopGroup).channel(NioSocketChannel.class)10                     .handler(new MyClientInitializer());11 12             ChannelFuture channelFuture = bootstrap.connect("localhost",8899).sync();13             channelFuture.channel().closeFuture().sync();14         }finally {15             eventLoopGroup.shutdownGracefully();16         }17 18 19     }20 21 }

 

client初始化類 ： 

 

 1 public class MyClientInitializer extends ChannelInitializer<SocketChannel>{ 2     @Override 3     protected void initChannel(SocketChannel ch) throws Exception { 4         ChannelPipeline channelPipeline = ch.pipeline(); 5         //解碼器 6         channelPipeline.addLast(new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE,0,4,0,4)); 7         //訊息 加header 8         channelPipeline.addLast(new LengthFieldPrepender(4)); 9         channelPipeline.addLast(new StringDecoder(CharsetUtil.UTF_8));10         channelPipeline.addLast(new StringEncoder(CharsetUtil.UTF_8));11         channelPipeline.addLast(new MyClientHandler());  //自己的處理器12     }13 }

 

client業務處理handler ：

 

 1 public class MyClientHandler extends SimpleChannelInboundHandler<String>{ 2     @Override 3     protected void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception { 4         System.out.println(ctx.channel().remoteAddress()); 5         System.out.println("client output "+msg); 6         ctx.writeAndFlush("from client "+ LocalDateTime.now()); 7  8     } 9 10     @Override11     public void channelActive(ChannelHandlerContext ctx) throws Exception {12         ctx.writeAndFlush("來自用戶端的問候！！");13     }14 15     @Override16     public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {17         cause.printStackTrace();18         ctx.close();19     }20 }

 

Netty的socket編程(四)