深圳分销网站设计价格,门户网站内容维护流程,wordpress数据控查看密码,私人定制哪个网站做的比较好1.pipeline调用handler的源码 //pipeline得到双向链表的头,next到尾部, 2.心跳源码 主要分析IdleStateHandler3个定时任务内部类 //考虑了网络传输慢导致出站慢的情况 //超时重新发送,然后关闭 ReadTimeoutHandler(继承IdleStateHandler 直接关闭连接)和WriteTimeoutHandler(继…1.pipeline调用handler的源码 //pipeline得到双向链表的头,next到尾部, 2.心跳源码 主要分析IdleStateHandler3个定时任务内部类 //考虑了网络传输慢导致出站慢的情况 //超时重新发送,然后关闭 ReadTimeoutHandler(继承IdleStateHandler 直接关闭连接)和WriteTimeoutHandler(继承ChannelOutboundHandlerAdapter 使用定时任务来完成) //NioEventLoop进行事件循环 Overrideprotected void run() {for (;;) {try {switch (selectStrategy.calculateStrategy(selectNowSupplier, hasTasks())) {case SelectStrategy.CONTINUE:continue;case SelectStrategy.SELECT:select(wakenUp.getAndSet(false));if (wakenUp.get()) {selector.wakeup();}// fall throughdefault:}cancelledKeys 0;needsToSelectAgain false;final int ioRatio this.ioRatio; //默认 50if (ioRatio 100) { //如果被占用,就处理事件try {processSelectedKeys();} finally {// Ensure we always run tasks.runAllTasks(); //执行任务}} else { //如果没有被占用final long ioStartTime System.nanoTime();try {processSelectedKeys(); //选择一个key} finally {// Ensure we always run tasks.final long ioTime System.nanoTime() - ioStartTime;runAllTasks(ioTime * (100 - ioRatio) / ioRatio); //ioRatio默认是50 ,计算出来是1.所以定时任务执行了 ioTime没有响应的时间(妙啊,如果执行1s或者是其他时间那可能还是检测不到心跳)}}} catch (Throwable t) {handleLoopException(t);}// Always handle shutdown even if the loop processing threw an exception.try {if (isShuttingDown()) {closeAll();if (confirmShutdown()) {return;}}} catch (Throwable t) {handleLoopException(t);}}}//IdleStateHandler
3.eventLoop执行定时任务的源代码(传入并执行队列) 1.select 默认阻塞1秒 4.任务加入异步线程池(处理耗时任务时)(因为执行任务读写 和执行读写后执行Loop任务是同一个线程) 就不会阻塞netty的IO 1.handler加入线程池(自己创建group线程池) 2.context加入线程池 /** Copyright 2012 The Netty Project** The Netty Project licenses this file to you under the Apache License,* version 2.0 (the License); you may not use this file except in compliance* with the License. You may obtain a copy of the License at:** http://www.apache.org/licenses/LICENSE-2.0** Unless required by applicable law or agreed to in writing, software* distributed under the License is distributed on an AS IS BASIS, WITHOUT* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the* License for the specific language governing permissions and limitations* under the License.*/
package source.echo2;import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandler.Sharable;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.util.CharsetUtil;
import io.netty.util.concurrent.DefaultEventExecutorGroup;
import io.netty.util.concurrent.EventExecutorGroup;import java.util.concurrent.Callable;/*** Handler implementation for the echo server.*/
Sharable
public class EchoServerHandler extends ChannelInboundHandlerAdapter {// group 就是充当业务线程池可以将任务提交到该线程池// 这里我们创建了16个线程static final EventExecutorGroup group new DefaultEventExecutorGroup(16);Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {System.out.println(EchoServer Handler 的线程是 Thread.currentThread().getName());//按照原来的方法处理耗时任务//解决方案2 用户程序自定义的普通任务ctx.channel().eventLoop().execute(new Runnable() {Overridepublic void run() {try {Thread.sleep(5 * 1000);//输出线程名System.out.println(EchoServerHandler execute 线程是 Thread.currentThread().getName());ctx.writeAndFlush(Unpooled.copiedBuffer(hello, 客户端~(^ω^)喵2, CharsetUtil.UTF_8));} catch (Exception ex) {System.out.println(发生异常 ex.getMessage());}}});ctx.channel().eventLoop().execute(new Runnable() {Overridepublic void run() {try {Thread.sleep(5 * 1000);//输出线程名System.out.println(EchoServerHandler execute 线程2是 Thread.currentThread().getName());ctx.writeAndFlush(Unpooled.copiedBuffer(hello, 客户端~(^ω^)喵2, CharsetUtil.UTF_8));} catch (Exception ex) {System.out.println(发生异常 ex.getMessage());}}});//方式1
// //将任务提交到 group线程池
// group.submit(new CallableObject() {
// Override
// public Object call() throws Exception {
//
// //接收客户端信息ByteBuf buf (ByteBuf) msg;byte[] bytes new byte[buf.readableBytes()];buf.readBytes(bytes);String body new String(bytes, UTF-8);//休眠10秒Thread.sleep(10 * 1000);
// System.out.println(group.submit 的 call 线程是 Thread.currentThread().getName());
// ctx.writeAndFlush(Unpooled.copiedBuffer(hello, 客户端~(^ω^)喵2, CharsetUtil.UTF_8));
// return null;
//
// }
// });
//
// //将任务提交到 group线程池
// group.submit(new CallableObject() {
// Override
// public Object call() throws Exception {
//
// //接收客户端信息
// ByteBuf buf (ByteBuf) msg;
// byte[] bytes new byte[buf.readableBytes()];
// buf.readBytes(bytes);
// String body new String(bytes, UTF-8);
// //休眠10秒
// Thread.sleep(10 * 1000);
// System.out.println(group.submit 的 call 线程是 Thread.currentThread().getName());
// ctx.writeAndFlush(Unpooled.copiedBuffer(hello, 客户端~(^ω^)喵2, CharsetUtil.UTF_8));
// return null;
//
// }
// });
//
//
// //将任务提交到 group线程池
// group.submit(new CallableObject() {
// Override
// public Object call() throws Exception {
//
// //接收客户端信息
// ByteBuf buf (ByteBuf) msg;
// byte[] bytes new byte[buf.readableBytes()];
// buf.readBytes(bytes);
// String body new String(bytes, UTF-8);
// //休眠10秒
// Thread.sleep(10 * 1000);
// System.out.println(group.submit 的 call 线程是 Thread.currentThread().getName());
// ctx.writeAndFlush(Unpooled.copiedBuffer(hello, 客户端~(^ω^)喵2, CharsetUtil.UTF_8));
// return null;
//
// }
// });//普通方式//接收客户端信息ByteBuf buf (ByteBuf) msg;byte[] bytes new byte[buf.readableBytes()];buf.readBytes(bytes);String body new String(bytes, UTF-8);//休眠10秒Thread.sleep(10 * 1000);System.out.println(普通调用方式的 线程是 Thread.currentThread().getName());ctx.writeAndFlush(Unpooled.copiedBuffer(hello, 客户端~(^ω^)喵2, CharsetUtil.UTF_8));System.out.println(go on );}Overridepublic void channelReadComplete(ChannelHandlerContext ctx) {ctx.flush();}Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {// Close the connection when an exception is raised.//cause.printStackTrace();ctx.close();}
}5.netty源码 //面试 1.连接 ServerBootstrap空的构造器 作用为初始化类的成员 //启动bind 6.RPC(remote procedure call) call function like local machine 1.usual framework , ali Dubbo google gRPC ,Go rpcx apache thrift ,spring cloud pic 17.rpc procedure imitate dubbo RPC 通过jdk反射实现 // server handler规定 msg开头是规定的字符串(或者协议) msg.toString().startsWith(“helloService#hello”) //callable可以在服务器和客户端之间使用,wait()然后notify() (在同一机器) //read调用只一次,然后调用call(netty的pipeline自动调用) //server和client,只需按照需要的名字来调用 //下面是客户端传递参数给服务端,然后服务端调用被代理的实现的接口
//创建消费者,调用远程服务
public class ClientBootstrap {//这里定义协议头(调用的方法名)public static final String providerName HelloService#hello#;public static void main(String[] args) throws Exception{//创建一个消费者NettyClient customer new NettyClient();//创建代理对象HelloService service (HelloService) customer.getBean(HelloService.class, providerName);for (;;) {Thread.sleep(2 * 1000);//通过代理对象调用服务提供者的方法(服务)String res service.hello(你好 dubbo~);System.out.println(调用的结果 res res);}}
}//创建客户端创建代理对象,和初始化客户端添加handler
public class NettyClient {//创建线程池private static ExecutorService executor Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());private static NettyClientHandler client;private int count 0;//编写方法使用代理模式获取一个代理对象public Object getBean(final Class? serivceClass, final String providerName) {return Proxy.newProxyInstance(Thread.currentThread().getContextClassLoader(),new Class?[]{serivceClass}, (proxy, method, args) - {System.out.println((proxy, method, args) 进入.... (count) 次);//{} 部分的代码客户端每调用一次 hello, 就会进入到该代码if (client null) {initClient();}//设置要发给服务器端的信息//providerName 协议头 args[0] 就是客户端调用api hello(???), 参数client.setPara(providerName args[0]);return executor.submit(client).get();});}//初始化客户端private static void initClient() {client new NettyClientHandler();//创建EventLoopGroupNioEventLoopGroup group new NioEventLoopGroup();Bootstrap bootstrap new Bootstrap();bootstrap.group(group).channel(NioSocketChannel.class).option(ChannelOption.TCP_NODELAY, true).handler(new ChannelInitializerSocketChannel() {Overrideprotected void initChannel(SocketChannel ch) throws Exception {ChannelPipeline pipeline ch.pipeline();pipeline.addLast(new StringDecoder());pipeline.addLast(new StringEncoder());pipeline.addLast(client);}});try {bootstrap.connect(127.0.0.1, 7000).sync();} catch (Exception e) {e.printStackTrace();}}
}
//客户端handler,处理来自服务器的请求,服务器有数据通知线程,没有就等待public class NettyClientHandler extends ChannelInboundHandlerAdapter implements Callable {private ChannelHandlerContext context;//上下文private String result; //返回的结果private String para; //客户端调用方法时传入的参数//与服务器的连接创建后就会被调用, 这个方法是第一个被调用(1)Overridepublic void channelActive(ChannelHandlerContext ctx) throws Exception {System.out.println( channelActive 被调用 );context ctx; //因为我们在其它方法会使用到 ctx}//收到服务器的数据后调用方法 (4)//Overridepublic synchronized void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {System.out.println( channelRead 被调用 );result msg.toString();notify(); //服务器返回数据,唤醒等待的线程}Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {ctx.close();}//被代理对象调用, 发送数据给服务器- wait - 等待被唤醒(channelRead) - 返回结果 (3)-》5Overridepublic synchronized Object call() throws Exception {System.out.println( call1 被调用 );context.writeAndFlush(para); //这里的context是client自己的,//进行waitwait(); //等待channelRead 方法获取到服务器的结果后唤醒System.out.println( call2 被调用 );return result; //服务方返回的结果}//(2)void setPara(String para) {System.out.println( setPara );this.para para;}
}//创建服务器端,添加服务器handler
public class NettyServer {public static void startServer(String hostName, int port) {startServer0(hostName,port);}//编写一个方法完成对NettyServer的初始化和启动private static void startServer0(String hostname, int port) {EventLoopGroup bossGroup new NioEventLoopGroup(1);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 {ChannelPipeline pipeline ch.pipeline();pipeline.addLast(new StringDecoder());pipeline.addLast(new StringEncoder());pipeline.addLast(new NettyServerHandler()); //业务处理器}});ChannelFuture channelFuture serverBootstrap.bind(hostname, port).sync();System.out.println(服务提供方开始提供服务~~);channelFuture.channel().closeFuture().sync();}catch (Exception e) {e.printStackTrace();}finally {bossGroup.shutdownGracefully();workerGroup.shutdownGracefully();}}public static void main(String[] args) {//代码代填..NettyServer.startServer(127.0.0.1, 7000);}
}
//服务器handler,如果接收到客户端的请求,得到字符,传入参数调用实现类方法public class NettyServerHandler extends ChannelInboundHandlerAdapter {Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {//获取客户端发送的消息并调用服务System.out.println(msg msg);//客户端在调用服务器的api 时我们需要定义一个协议//比如我们要求 每次发消息是都必须以某个字符串开头 HelloService#hello#你好if(msg.toString().startsWith(ClientBootstrap.providerName)) {msg.toString().lastIndexOf(#)String substring msg.toString().substring(msg.toString().lastIndexOf(#) 1);String result new HelloServiceImpl().hello(substring);ctx.writeAndFlush(result); //向客户端写回返回的结果}}Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {ctx.close();}
}//接口(客户端需要,使用jdk代理可以代理接口,使用cglib可以直接代理类) //这个是接口是服务提供方和 服务消费方都需要
public interface HelloService {String hello(String mes);
}//实现类
public class HelloServiceImpl implements HelloService {private static int count 0;//当有消费方调用该方法时 就返回一个结果Overridepublic String hello(String mes) {System.out.println(收到客户端消息 mes);//根据mes 返回不同的结果if(mes ! null) {return 你好客户端, 我已经收到你的消息 [ mes ] 第 (count) 次;} else {return 你好客户端, 我已经收到你的消息 ;}}
}
