如何用手机做音乐网站,商城网站的主要模块,手机网站导航条,东营组建网站文章目录 概念Server CodeClient CodeInboundHandler和OutboundHandler的执行顺序在InboundHandler中不触发fire方法InboundHandler和OutboundHandler的执行顺序如果把OutboundHandler放在InboundHandler的后面#xff0c;OutboundHandler会执行吗 概念 我们知道当boss线程监控… 文章目录 概念Server CodeClient CodeInboundHandler和OutboundHandler的执行顺序在InboundHandler中不触发fire方法InboundHandler和OutboundHandler的执行顺序如果把OutboundHandler放在InboundHandler的后面OutboundHandler会执行吗 概念 我们知道当boss线程监控到绑定端口上有accept事件此时会为该socket连接实例化Pipeline并将InboundHandler和OutboundHandler按序加载到Pipeline中然后将该socket连接也就是Channel对象挂载到selector上。
一个selector对应一个线程该线程会轮询所有挂载在他身上的socket连接有没有read或write事件然后通过线程池去执行Pipeline的业务流。
selector如何查询哪些socket连接有read或write事件主要取决于调用操作系统的哪种IO多路复用内核
如果是select注意此处的select是指操作系统内核的select IO多路复用不是netty的seletor对象那么将会遍历所有socket连接依次询问是否有read或write事件最终操作系统内核将所有IO事件的socket连接返回给netty进程当有很多socket连接时这种方式将会大大降低性能因为存在大量socket连接的遍历和内核内存的拷贝。如果是epoll性能将会大幅提升因为它基于完成端口事件已经维护好有IO事件的socket连接列表selector直接取走无需遍历也少掉内核内存拷贝带来的性能损耗 在Netty中Inbound和Outbound是两个重要的概念用于描述数据在ChannelPipeline中的流动方向。
Inbound入站指的是数据从网络传输到应用程序即数据从远程主机进入本地主机。在ChannelPipeline中Inbound数据会依次经过Pipeline中的每个ChannelHandler进行处理直到到达Pipeline的末尾。
Outbound出站指的是数据从应用程序传输到网络即数据从本地主机发送到远程主机。在ChannelPipeline中Outbound数据会从Pipeline的末尾开始逆序经过Pipeline中的每个ChannelHandler进行处理直到到达Pipeline的起始位置。
Inbound和Outbound的区别在于数据的流动方向。Inbound数据是从网络进入应用程序而Outbound数据是从应用程序发送到网络。这意味着Inbound数据是应用程序接收和处理外部数据的入口而Outbound数据是应用程序发送数据到外部的出口。
虽然Inbound和Outbound描述了数据的不同流动方向但它们之间也存在联系。在ChannelPipeline中Inbound和Outbound数据可以相互影响和交互。例如一个ChannelHandler可以在处理Inbound数据时生成Outbound数据作为响应或者在处理Outbound数据时修改Inbound数据的内容。
总结起来Inbound和Outbound是描述数据在ChannelPipeline中流动方向的概念。Inbound数据是从网络进入应用程序Outbound数据是从应用程序发送到网络。它们在ChannelPipeline中相互影响和交互共同实现网络数据的处理和传输。 Pipeline的责任链是通过ChannelHandlerContext对象串联的ChannelHandlerContext对象里封装了ChannelHandler对象通过prev和next节点实现双向链表。Pipeline的首尾节点分别是head和tail当selector轮询到socket有read事件时将会触发Pipeline责任链从head开始调起第一个InboundHandler的ChannelRead事件接着通过fire方法依次触发Pipeline上的下一个ChannelHandler . ChannelHandler分为InbounHandler和OutboundHandler
InboundHandler用来处理接收消息OutboundHandler用来处理发送消息。
head的ChannelHandler既是InboundHandler又是OutboundHandler无论是read还是write都会经过head所以head封装了unsafe方法用来操作socket的read和write。tail的ChannelHandler只是InboundHandlerread的Pipleline处理将会最终到达tail 演示之前我们先附一下代码
Server Code
package com.artisan.pipeline.inout;import com.artisan.pipeline.inout.handler.*;
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;/*** author 小工匠* version 1.0* mark: show me the code , change the world*/
public class ArtisanEchoServer {private int port;public ArtisanEchoServer(int port) {this.port port;}private void run() {EventLoopGroup bossGroup new NioEventLoopGroup();EventLoopGroup workerGroup new NioEventLoopGroup();try {ServerBootstrap serverBootstrap new ServerBootstrap();serverBootstrap.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class).childHandler(new ChannelInitializerSocketChannel() {Overrideprotected void initChannel(SocketChannel ch) throws Exception {ch.pipeline().addLast(new EchoOutboundHandler3());ch.pipeline().addLast(new EchoOutboundHandler2());ch.pipeline().addLast(new EchoOutboundHandler1());ch.pipeline().addLast(new EchoInboundHandler1());ch.pipeline().addLast(new EchoInboundHandler2());ch.pipeline().addLast(new EchoInboundHandler3());}}).option(ChannelOption.SO_BACKLOG, 10000).childOption(ChannelOption.SO_KEEPALIVE, true);System.out.println(EchoServer正在启动...);ChannelFuture channelFuture serverBootstrap.bind(port).sync();System.out.println(EchoServer绑定端口: port);channelFuture.channel().closeFuture().sync();System.out.println(EchoServer已关闭.);} catch (Exception e) {e.printStackTrace();} finally {bossGroup.shutdownGracefully();workerGroup.shutdownGracefully();}}public static void main(String[] args) {int port 1234;if (args ! null args.length 0) {try {port Integer.parseInt(args[0]);} catch (Exception e) {e.printStackTrace();}}ArtisanEchoServer server new ArtisanEchoServer(port);server.run();}
} 6个handler演示如下
package com.artisan.pipeline.inout.handler;import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.util.CharsetUtil;/*** author 小工匠* version 1.0* mark: show me the code , change the world*/
public class EchoInboundHandler1 extends ChannelInboundHandlerAdapter {Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {System.out.println();System.out.println(进入 EchoInboundHandler1.channelRead);String data ((ByteBuf) msg).toString(CharsetUtil.UTF_8);System.out.println(EchoInboundHandler1.channelRead 收到数据 data);ctx.fireChannelRead(Unpooled.copiedBuffer([EchoInboundHandler1] data, CharsetUtil.UTF_8));System.out.println(退出 EchoInboundHandler1 channelRead);System.out.println();}Overridepublic void channelReadComplete(ChannelHandlerContext ctx) throws Exception {System.out.println([EchoInboundHandler1.channelReadComplete]);}Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {System.out.println([EchoInboundHandler1.exceptionCaught] cause.toString());}
}
package com.artisan.pipeline.inout.handler;import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.util.CharsetUtil;/*** author 小工匠* version 1.0* mark: show me the code , change the world*/
public class EchoInboundHandler2 extends ChannelInboundHandlerAdapter {Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {System.out.println();System.out.println(进入 EchoInboundHandler2.channelRead);String data ((ByteBuf) msg).toString(CharsetUtil.UTF_8);System.out.println(EchoInboundHandler2.channelRead 接收到数据 data);//ctx.writeAndFlush(Unpooled.copiedBuffer([第一次write] [EchoInboundHandler2] data, CharsetUtil.UTF_8));ctx.channel().writeAndFlush(Unpooled.copiedBuffer(测试一下channel().writeAndFlush, CharsetUtil.UTF_8));ctx.fireChannelRead(Unpooled.copiedBuffer([ArtisanEchoOutboundHandler2] data, CharsetUtil.UTF_8));System.out.println(退出 EchoInboundHandler2 channelRead);System.out.println();}Overridepublic void channelReadComplete(ChannelHandlerContext ctx) throws Exception {System.out.println([EchoInboundHandler2.channelReadComplete]读取数据完成);}Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {System.out.println([EchoInboundHandler2.exceptionCaught]);}
}
package com.artisan.pipeline.inout.handler;import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.util.CharsetUtil;/*** author 小工匠* version 1.0* mark: show me the code , change the world*/
public class EchoInboundHandler3 extends ChannelInboundHandlerAdapter {Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {System.out.println();System.out.println(进入 EchoInboundHandler3.channelRead);String data ((ByteBuf)msg).toString(CharsetUtil.UTF_8);System.out.println(EchoInboundHandler3.channelRead 接收到数据 data);//ctx.writeAndFlush(Unpooled.copiedBuffer([第二次write] [EchoInboundHandler3] data, CharsetUtil.UTF_8));ctx.fireChannelRead(msg);System.out.println(退出 EchoInboundHandler3 channelRead);System.out.println();}Overridepublic void channelReadComplete(ChannelHandlerContext ctx) throws Exception {System.out.println([EchoInboundHandler3.channelReadComplete]读取数据完成);}Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {System.out.println([EchoInboundHandler3.exceptionCaught]);}}
package com.artisan.pipeline.inout.handler;import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;/*** author 小工匠* version 1.0* mark: show me the code , change the world*/
public class EchoOutboundHandler1 extends ChannelOutboundHandlerAdapter {Overridepublic void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {System.out.println(进入 EchoOutboundHandler1.write);//ctx.writeAndFlush(Unpooled.copiedBuffer([第一次write中的write], CharsetUtil.UTF_8));
// ctx.channel().writeAndFlush(Unpooled.copiedBuffer(在OutboundHandler里测试一下channel().writeAndFlush, CharsetUtil.UTF_8));ctx.write(msg);System.out.println(退出 EchoOutboundHandler1.write);}}
package com.artisan.pipeline.inout.handler;import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;/*** author 小工匠* version 1.0* mark: show me the code , change the world*/
public class EchoOutboundHandler2 extends ChannelOutboundHandlerAdapter {Overridepublic void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {System.out.println(进入 EchoOutboundHandler2.write);//ctx.writeAndFlush(Unpooled.copiedBuffer([第二次write中的write], CharsetUtil.UTF_8));ctx.write(msg);System.out.println(退出 EchoOutboundHandler2.write);}
}
package com.artisan.pipeline.inout.handler;import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelOutboundHandlerAdapter;
import io.netty.channel.ChannelPromise;/*** author 小工匠* version 1.0* mark: show me the code , change the world*/
public class EchoOutboundHandler3 extends ChannelOutboundHandlerAdapter {Overridepublic void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) throws Exception {System.out.println(进入 EchoOutboundHandler3.write);ctx.write(msg);System.out.println(退出 EchoOutboundHandler3.write);}}
Client Code
package com.artisan.netty4.client;import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;/*** author 小工匠* version 1.0* description: 客户端启动程序* mark: show me the code , change the world*/
public class ArtisanClient {public static void main(String[] args) throws Exception {NioEventLoopGroup eventExecutors new NioEventLoopGroup();try {//创建bootstrap对象配置参数Bootstrap bootstrap new Bootstrap();//设置线程组bootstrap.group(eventExecutors)//设置客户端的通道实现类型.channel(NioSocketChannel.class)//使用匿名内部类初始化通道.handler(new ChannelInitializerSocketChannel() {Overrideprotected void initChannel(SocketChannel ch) throws Exception {//添加客户端通道的处理器ch.pipeline().addLast(new ArtisanClientHandler());}});System.out.println(客户端准备就绪);//连接服务端ChannelFuture channelFuture bootstrap.connect(127.0.0.1, 1234).sync();//对通道关闭进行监听channelFuture.channel().closeFuture().sync();} finally {//关闭线程组eventExecutors.shutdownGracefully();}}
}
package com.artisan.netty4.client;import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.util.CharsetUtil;/*** author 小工匠* version 1.0* description: 通用handler处理I/O事件* mark: show me the code , change the world*/
ChannelHandler.Sharable
public class ArtisanClientHandler extends ChannelInboundHandlerAdapter {Overridepublic void channelActive(ChannelHandlerContext ctx) throws Exception {//发送消息到服务端ctx.writeAndFlush(Unpooled.copiedBuffer(msg send from client 2 server , CharsetUtil.UTF_8));System.out.println(客户端发消息给服务端结束);System.out.println();}Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {//接收服务端发送过来的消息ByteBuf byteBuf (ByteBuf) msg;System.out.println(收到服务端 ctx.channel().remoteAddress() 的消息 byteBuf.toString(CharsetUtil.UTF_8));}} InboundHandler和OutboundHandler的执行顺序
在InboundHandler中不触发fire方法
ArtisanEchoServer#run 中我们先进存在InboundHandler 先启动server 在启动Client我们测试一下 我们可以看到 InboundHandler2没有调用fire事件InboundHandler3没有被执行 InboundHandler是通过fire事件决定是否要执行下一个InboundHandler如果InboundHandler没有调用fire事件那么后续的Pipeline中的Handler将不会执行。
我们来看下源码 InboundHandler和OutboundHandler的执行顺序 加入Pipeline的ChannelHandler的顺序如上。
别忘了放开EchoInboundHandler2 ctx.fireChannelRead(Unpooled.copiedBuffer([ArtisanEchoOutboundHandler2] data, CharsetUtil.UTF_8));我们来验证下 执行顺序如上。
InboundHandler1 InboundHandler2 OutboundHandler1 OutboundHander2 OutboundHandler3 InboundHandler31、InboundHandler是按照Pipleline的加载顺序顺序执行。
2、OutboundHandler是按照Pipeline的加载顺序逆序执行。 如果把OutboundHandler放在InboundHandler的后面OutboundHandler会执行吗 其中EchoInboundHandler2 先不要给客户端发送数据先屏蔽掉。
public class EchoInboundHandler2 extends ChannelInboundHandlerAdapter {Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {System.out.println(进入 EchoInboundHandler2.channelRead);String data ((ByteBuf) msg).toString(CharsetUtil.UTF_8);System.out.println(EchoInboundHandler2.channelRead 接收到数据 data);
// ctx.writeAndFlush(Unpooled.copiedBuffer([第一次write] [EchoInboundHandler2] data, CharsetUtil.UTF_8));
// ctx.channel().writeAndFlush(Unpooled.copiedBuffer(测试一下channel().writeAndFlush, CharsetUtil.UTF_8));ctx.fireChannelRead(Unpooled.copiedBuffer([ArtisanEchoOutboundHandler2] data, CharsetUtil.UTF_8));System.out.println(退出 EchoInboundHandler2 channelRead);}
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