java | 分工细化

java | 分工细化 | 犀牛的博客

相对于 java | IO 任务 进行细化。

package com.redisc;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.string.StringEncoder;

import java.io.IOException;
import java.net.InetSocketAddress;

public class Client {
    public static void main(String[] args) throws IOException, InterruptedException {
        Channel channel = new Bootstrap()
                .group(new NioEventLoopGroup())
                .channel(NioSocketChannel.class)
                .handler(new ChannelInitializer<NioSocketChannel>() {
                    @Override
                    protected void initChannel(NioSocketChannel nioSocketChannel) throws Exception {
                        nioSocketChannel.pipeline().addLast(new StringEncoder());

}
                }).connect(new InetSocketAddress("localhost", 8000))
                .sync().channel();
        channel.writeAndFlush("hello");
    }
}

26 处打断点。

package com.redisc;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import lombok.extern.slf4j.Slf4j;

import java.io.IOException;
import java.nio.charset.Charset;

import org.slf4j.LoggerFactory;
import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.Logger;


@Slf4j
public class Run {

public static void main(String[] args) throws IOException {
        LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
        Logger rootLogger = loggerContext.getLogger("io.netty");
        rootLogger.setLevel(ch.qos.logback.classic.Level.OFF);

new ServerBootstrap()
                // group 的两个参数
                // boss 和 worker
                // boss 只负责 ServerSocketChannel 上 accept 事件
                // worker 只负责 socketChannel 上读写
                // 请参考 https://benpaodewoniu.github.io/2023/01/08/java184/
                .group(new NioEventLoopGroup(), new NioEventLoopGroup(2))
                .channel(NioServerSocketChannel.class)
                .childHandler(new ChannelInitializer<NioSocketChannel>() {

@Override
                    protected void initChannel(NioSocketChannel nioSocketChannel) throws Exception {
                        nioSocketChannel.pipeline().addLast(new ChannelInboundHandlerAdapter() {
                            @Override
                            public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
                                ByteBuf buffer = (ByteBuf) msg;
                                log.debug(buffer.toString(Charset.defaultCharset()));
                            }
                        });
                    }

}).bind(8000);
    }

}

• 开启服务器
• 开启客户端
  • 到断点处，自己发送信息
  • 一共开启 3 个独立的客户端「客户端不关闭」

服务端输出

23:16:22.960 [nioEventLoopGroup-3-1] DEBUG com.redisc.Run - hello
23:23:36.518 [nioEventLoopGroup-3-2] DEBUG com.redisc.Run - 123
23:24:04.125 [nioEventLoopGroup-3-1] DEBUG com.redisc.Run - 222

因为，worker 线程只有两个，所以，是两个线程分别处理。

但是，这个方式有一个缺陷，就是，当某一个任务处理时常非常长的时候，其他的任务得不到处理。

优化服务器

package com.redisc;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import lombok.extern.slf4j.Slf4j;

import java.io.IOException;
import java.nio.charset.Charset;

import org.slf4j.LoggerFactory;
import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.Logger;


@Slf4j
public class Run {

public static void main(String[] args) throws IOException {
        LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
        Logger rootLogger = loggerContext.getLogger("io.netty");
        rootLogger.setLevel(ch.qos.logback.classic.Level.OFF);

EventLoopGroup eventLoopGroup = new DefaultEventLoopGroup();

new ServerBootstrap()
                // group 的两个参数
                // boss 和 worker
                // boss 只负责 ServerSocketChannel 上 accept 事件
                // worker 只负责 socketChannel 上读写
                // 请参考 https://benpaodewoniu.github.io/2023/01/08/java184/
                .group(new NioEventLoopGroup(), new NioEventLoopGroup(2))
                .channel(NioServerSocketChannel.class)
                .childHandler(new ChannelInitializer<NioSocketChannel>() {

@Override
                    protected void initChannel(NioSocketChannel nioSocketChannel) throws Exception {
                        nioSocketChannel.pipeline().addLast("handler1",new ChannelInboundHandlerAdapter() {
                            @Override
                            public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
                                ByteBuf buffer = (ByteBuf) msg;
                                log.debug(buffer.toString(Charset.defaultCharset()));
                                ctx.fireChannelRead(msg); // 必须加上这句话才能传递给下一个 pipline
                            }
                        }).addLast(eventLoopGroup,"handler2",new ChannelInboundHandlerAdapter(){
                            @Override
                            public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
                                ByteBuf buffer = (ByteBuf) msg;
                                log.debug(buffer.toString(Charset.defaultCharset()));
                            }
                        });
                    }

}).bind(8000);
    }

}

这里又弄了一个 EventLoopGroup，并添加到了 pipeline 中，可以专门用来处理耗时时间长的操作。

开启一个客户端，输出如下

23:45:19.310 [nioEventLoopGroup-4-1] DEBUG com.redisc.Run - hello
23:45:19.318 [defaultEventLoopGroup-2-1] DEBUG com.redisc.Run - hello