标签：loop worker ble tin oev active extends str inbound
Netty入门之客户端与服务端通信(二)
一.简介
在上一篇博文中笔者写了关于Netty入门级的Hello World程序。书接上回，本博文是关于客户端与服务端的通信，感觉也没什么好说的了，直接上代码吧。
二.客户端与服务端的通信
2.1 服务端启动程序
public class MyServer { public static void main(String[] args) throws InterruptedException { EventLoopGroup bossGroup = new NioEventLoopGroup(); EventLoopGroup workerGroup = new NioEventLoopGroup(); try{ ServerBootstrap serverBootstrap = new ServerBootstrap(); serverBootstrap.group(bossGroup, workerGroup) .channel(NioServerSocketChannel.class) .childHandler(new MyInitializer()); ChannelFuture channelFuture = serverBootstrap.bind(8899).sync(); channelFuture.channel().closeFuture().sync(); }finally{ bossGroup.shutdownGracefully(); workerGroup.shutdownGracefully(); } } }
2.2 服务端通道初始化程序
public class MyInitializer extends ChannelInitializer<SocketChannel>{ @Override protected void initChannel(SocketChannel ch) throws Exception { ChannelPipeline pipeline = ch.pipeline(); /** * LengthFieldBasedFrameDecoder: 基于长度属性的帧解码器。 * 客户端传递过来的数据格式为： * BEFORE DECODE (14 bytes) AFTER DECODE (14 bytes) * +--------+----------------+ +--------+----------------+ * | Length | Actual Content |----->| Length | Actual Content | * | 0x000C | "HELLO, WORLD" | | 0x000C | "HELLO, WORLD" | * +--------+----------------+ +--------+----------------+ * 5个参数依次为：1.(maxFrameLength)每帧数据的最大长度. * 2.(lengthFieldOffset)length属性在帧中的偏移量。 * 3.(lengthFieldLength)length属性的长度，需要与客户端 LengthFieldPrepender设置的长度一致， * 值的取值只能为1, 2, 3, 4, 8 * 4.(lengthAdjustment)长度调节值, 当信息长度包含长度时候，用于修正信息的长度。 * 5.(initialBytesToStrip)在获取真实的内容的时候，需要忽略的长度(通常就是length的长度)。 * * 参考： http://blog.csdn.net/educast/article/details/47706599 */ pipeline.addLast("lengthFieldBasedFrameDecoder", new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 2, 0, 2)); /** * LengthFieldPrepender: length属性在帧中的长度。只能为1,2,3,4,8。 * 该值与对应的客户端(或者服务端)在解码时候使用LengthFieldBasedFrameDecoder中所指定的lengthFieldLength * 的值要保持一致。 */ pipeline.addLast("lengthFieldPrepender", new LengthFieldPrepender(3)); //StringDecoder字符串的解码器, 主要用于处理编码格式 pipeline.addLast("stringDecoder", new StringDecoder(CharsetUtil.UTF_8)); //StringDecoder字符串的编码器，主要用于指定字符串的编码格式 pipeline.addLast("stringEncoder", new StringEncoder(CharsetUtil.UTF_8)); pipeline.addLast(new MyHandler()); //自定义的Handler } }
2.3 自定义Handler
public class MyHandler extends SimpleChannelInboundHandler<String>{ @Override protected void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception { System.out.println(ctx.channel().remoteAddress() + ":" + msg); ctx.channel().writeAndFlush("from server: 草泥马"); } @Override public void handlerAdded(ChannelHandlerContext ctx) throws Exception { System.out.println(System.currentTimeMillis() + "********"); System.out.println("server handler added**********"); } @Override public void channelRegistered(ChannelHandlerContext ctx) throws Exception { System.out.println(System.currentTimeMillis() + "********"); System.out.println("server channel register****"); } @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { System.out.println(System.currentTimeMillis() + "********"); System.out.println("server channel actieve****"); } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { cause.printStackTrace(); ctx.close(); } }
2.4客户端启动程序
public class MyClient { public static void main(String[] args) throws InterruptedException { EventLoopGroup eventLoopGroup = new NioEventLoopGroup(); try{ Bootstrap bootstrap = new Bootstrap(); bootstrap.group(eventLoopGroup).channel(NioSocketChannel.class).handler(new ClientInitializer()); ChannelFuture channelFuture = bootstrap.connect("127.0.0.1", 8899).sync(); channelFuture.channel().closeFuture().sync(); }finally{ eventLoopGroup.shutdownGracefully(); } } }
2.5客户端通道初始化
public class ClientInitializer extends ChannelInitializer<SocketChannel>{ @Override protected void initChannel(SocketChannel ch) throws Exception { ChannelPipeline pipeline = ch.pipeline(); pipeline.addLast("lengthFieldBasedFrameDecoder", new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 2, 0, 2)); pipeline.addLast("lengthFieldPrepender", new LengthFieldPrepender(3)); pipeline.addLast("stringDecoder", new StringDecoder(CharsetUtil.UTF_8)); pipeline.addLast("stringEncoder", new StringEncoder(CharsetUtil.UTF_8)); pipeline.addLast(new MyClientHandler()); } }
2.5客户端自定义Handler
public class MyClientHandler extends SimpleChannelInboundHandler<String>{ @Override protected void channelRead0(ChannelHandlerContext ctx, String msg) throws Exception { System.out.println(ctx.channel().remoteAddress()); System.out.println(msg); ctx.channel().writeAndFlush("to Server: 草泥马"); } @Override public void channelActive(ChannelHandlerContext ctx) throws Exception { System.out.println(System.currentTimeMillis() + "..........."); ctx.channel().writeAndFlush("来自于客户端的问候！"); System.out.println("client channel Active..."); } @Override public void handlerAdded(ChannelHandlerContext ctx) throws Exception { System.out.println(System.currentTimeMillis() + "..........."); System.out.println("client hanlder added..."); } @Override public void channelRegistered(ChannelHandlerContext ctx) throws Exception { System.out.println(System.currentTimeMillis() + "..........."); System.out.println("client channel register..."); } @Override public void channelInactive(ChannelHandlerContext ctx) throws Exception { System.out.println("client channel inactive..."); } @Override public void channelUnregistered(ChannelHandlerContext ctx) throws Exception { System.out.println("client channel unregister..."); } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { cause.printStackTrace(); ctx.close(); } }
三. 运行测试
运行服务端启动代码，然后在运行客户端启动代码，就可以看见千万只"草泥马"在崩腾。
标签：loop worker ble tin oev active extends str inbound
原文地址：http://www.cnblogs.com/miller-zou/p/6995440.html
