Netty(四) 简化版Netty源码

简化版Netty源码

netty学习目录
一、Netty(一) NIO例子
二、Netty(二) netty服务端
三、Netty(三) Netty客户端+服务端
四、Netty(四) 简化版Netty源码
五、Netty(五)Netty5.x服务端
六、Netty(六) Netty Http 服务器例子
七、Netty(七) Netty服务端+客户端代码
八、Netty(八) Netty多客户端连接例子
九、Netty(九) Netty会话清除
十、Netty(十) Netty自定义编码器解码器
十一、Netty(十一) Netty对象传输

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package com.zqw.nio.netty.n3.pool;

import java.nio.channels.ServerSocketChannel;

public interface Boss {

    /**
     * 加入一个新的ServerSocket
     * @param serverChannel
     */
    public void registerAcceptChannelTask(ServerSocketChannel serverChannel);
}

package com.zqw.nio.netty.n3.pool;



import com.zqw.nio.netty.n3.NioServerBoss;
import com.zqw.nio.netty.n3.NioServerWorker;

import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicInteger;

public class NioSelectorRunnablePool {

    /**
     * boss线程数组
     */
    private final AtomicInteger bossIndex = new AtomicInteger();
    private Boss[] bosses;

    /**
     * worker线程数组
     */
    private final AtomicInteger workerIndex = new AtomicInteger();
    private Worker[] workeres;


    public NioSelectorRunnablePool(Executor boss, Executor worker) {
        initBoss(boss, 1);
        initWorker(worker, Runtime.getRuntime().availableProcessors() * 2);
    }

    /**
     * 初始化boss线程
     * @param boss
     * @param count
     */
    private void initBoss(Executor boss, int count) {
        this.bosses = new NioServerBoss[count];
        for (int i = 0; i < bosses.length; i++) {
            bosses[i] = new NioServerBoss(boss, "boss thread " + (i+1), this);
        }

    }

    /**
     * 初始化worker线程
     * @param worker
     * @param count
     */
    private void initWorker(Executor worker, int count) {
        this.workeres = new NioServerWorker[count];
        for (int i = 0; i < workeres.length; i++) {
            workeres[i] = new NioServerWorker(worker, "worker thread " + (i+1), this);
        }
    }

    /**
     * 获取一个worker
     * @return
     */
    public Worker nextWorker() {
         return workeres[Math.abs(workerIndex.getAndIncrement() % workeres.length)];

    }

    /**
     * 获取一个boss
     * @return
     */
    public Boss nextBoss() {
         return bosses[Math.abs(bossIndex.getAndIncrement() % bosses.length)];
    }

}

package com.zqw.nio.netty.n3.pool;

import java.nio.channels.SocketChannel;

public interface Worker {

    /**
     * 加入一个新的客户端会话
     * @param channel
     */
    public void registerNewChannelTask(SocketChannel channel);

}

package com.zqw.nio.netty.n3;

import com.zqw.nio.netty.n3.pool.NioSelectorRunnablePool;

import java.io.IOException;
import java.nio.channels.Selector;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicBoolean;


public abstract class AbstractNioSelector implements Runnable {

    /**
     * 线程池
     */
    private final Executor executor;

    /**
     * 选择器
     */
    protected Selector selector;

    /**
     * 选择器wakenUp状态标记
     */
    protected final AtomicBoolean wakenUp = new AtomicBoolean();

    /**
     * 任务队列
     */
    private final Queue taskQueue = new ConcurrentLinkedQueue();

    /**
     * 线程名称
     */
    private String threadName;

    /**
     * 线程管理对象
     */
    protected NioSelectorRunnablePool selectorRunnablePool;

    AbstractNioSelector(Executor executor, String threadName, NioSelectorRunnablePool selectorRunnablePool) {
        this.executor = executor;
        this.threadName = threadName;
        this.selectorRunnablePool = selectorRunnablePool;
        openSelector();
    }

    /**
     * 获取selector并启动线程
     */
    private void openSelector() {
        try {
            this.selector = Selector.open();
        } catch (IOException e) {
            throw new RuntimeException("Failed to create a selector.");
        }
        executor.execute(this);
    }

    @Override
    public void run() {

        Thread.currentThread().setName(this.threadName);

        while (true) {
            try {
                wakenUp.set(false);

                select(selector);

                processTaskQueue();

                process(selector);
            } catch (Exception e) {
                // ignore
            }
        }

    }

    /**
     * 注册一个任务并激活selector
     * 
     * @param task
     */
    protected final void registerTask(Runnable task) {
        taskQueue.add(task);

        Selector selector = this.selector;

        if (selector != null) {
            if (wakenUp.compareAndSet(false, true)) {
                selector.wakeup();
            }
        } else {
            taskQueue.remove(task);
        }
    }

    /**
     * 执行队列里的任务
     */
    private void processTaskQueue() {
        for (;;) {
            final Runnable task = taskQueue.poll();
            if (task == null) {
                break;
            }
            task.run();
        }
    }

    /**
     * 获取线程管理对象
     * @return
     */
    public NioSelectorRunnablePool getSelectorRunnablePool() {
        return selectorRunnablePool;
    }

    /**
     * select抽象方法
     * 
     * @param selector
     * @return
     * @throws IOException
     */
    protected abstract int select(Selector selector) throws IOException;

    /**
     * selector的业务处理
     * 
     * @param selector
     * @throws IOException
     */
    protected abstract void process(Selector selector) throws IOException;

}

package com.zqw.nio.netty.n3;

import java.io.IOException;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Set;
import java.util.concurrent.Executor;


import com.zqw.nio.netty.n3.pool.Boss;
import com.zqw.nio.netty.n3.pool.NioSelectorRunnablePool;
import com.zqw.nio.netty.n3.pool.Worker;


public class NioServerBoss extends AbstractNioSelector implements Boss {

    public NioServerBoss(Executor executor, String threadName, NioSelectorRunnablePool selectorRunnablePool) {
        super(executor, threadName, selectorRunnablePool);
    }

    @Override
    protected void process(Selector selector) throws IOException {
        Set selectedKeys = selector.selectedKeys();
        if (selectedKeys.isEmpty()) {
            return;
        }

        for (Iterator i = selectedKeys.iterator(); i.hasNext();) {
            SelectionKey key = i.next();
            i.remove();
            ServerSocketChannel server = (ServerSocketChannel) key.channel();
            // 新客户端
            SocketChannel channel = server.accept();
            // 设置为非阻塞
            channel.configureBlocking(false);
            // 获取一个worker
            Worker nextworker = getSelectorRunnablePool().nextWorker();
            // 注册新客户端接入任务
            nextworker.registerNewChannelTask(channel);

            System.out.println("新客户端链接");
        }
    }


    public void registerAcceptChannelTask(final ServerSocketChannel serverChannel){
         final Selector selector = this.selector;
         registerTask(new Runnable() {
            @Override
            public void run() {
                try {
                    //注册serverChannel到selector
                    serverChannel.register(selector, SelectionKey.OP_ACCEPT);
                } catch (ClosedChannelException e) {
                    e.printStackTrace();
                }
            }
        });
    }

    @Override
    protected int select(Selector selector) throws IOException {
        return selector.select();
    }

}

package com.zqw.nio.netty.n3;

import com.zqw.nio.netty.n3.pool.NioSelectorRunnablePool;
import com.zqw.nio.netty.n3.pool.Worker;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.ClosedChannelException;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.util.Iterator;
import java.util.Set;
import java.util.concurrent.Executor;

public class NioServerWorker extends AbstractNioSelector implements Worker {

    public NioServerWorker(Executor executor, String threadName, NioSelectorRunnablePool selectorRunnablePool) {
        super(executor, threadName, selectorRunnablePool);
    }

    @Override
    protected void process(Selector selector) throws IOException {
        Set selectedKeys = selector.selectedKeys();
        if (selectedKeys.isEmpty()) {
            return;
        }
        Iterator ite = this.selector.selectedKeys().iterator();
        while (ite.hasNext()) {
            SelectionKey key = (SelectionKey) ite.next();
            // 移除，防止重复处理
            ite.remove();

            // 得到事件发生的Socket通道
            SocketChannel channel = (SocketChannel) key.channel();

            // 数据总长度
            int ret = 0;
            boolean failure = true;
            ByteBuffer buffer = ByteBuffer.allocate(1024);
            //读取数据
            try {
                ret = channel.read(buffer);
                failure = false;
            } catch (Exception e) {
                // ignore
            }
            //判断是否连接已断开
            if (ret <= 0 || failure) {
                key.cancel();
                System.out.println("客户端断开连接");
            }else{
                 System.out.println("收到数据:" + new String(buffer.array()));

                //回写数据
                ByteBuffer outBuffer = ByteBuffer.wrap("收到\n".getBytes());
                channel.write(outBuffer);// 将消息回送给客户端
            }
        }
    }

    /**
     * 加入一个新的socket客户端
     */
    public void registerNewChannelTask(final SocketChannel channel){
         final Selector selector = this.selector;
         registerTask(new Runnable() {
            @Override
            public void run() {
                try {
                    //将客户端注册到selector中
                    channel.register(selector, SelectionKey.OP_READ);
                } catch (ClosedChannelException e) {
                    e.printStackTrace();
                }
            }
        });
    }

    @Override
    protected int select(Selector selector) throws IOException {
        return selector.select(500);
    }

}

package com.zqw.nio.netty.n3;

import com.zqw.nio.netty.n3.pool.Boss;
import com.zqw.nio.netty.n3.pool.NioSelectorRunnablePool;

import java.net.SocketAddress;
import java.nio.channels.ServerSocketChannel;

public class ServerBootstrap {

private NioSelectorRunnablePool selectorRunnablePool;

    public ServerBootstrap(NioSelectorRunnablePool selectorRunnablePool) {
        this.selectorRunnablePool = selectorRunnablePool;
    }

    /**
     * 绑定端口
     * @param localAddress
     */
    public void bind(final SocketAddress localAddress){
        try {
            // 获得一个ServerSocket通道
            ServerSocketChannel serverChannel = ServerSocketChannel.open();
            // 设置通道为非阻塞
            serverChannel.configureBlocking(false);
            // 将该通道对应的ServerSocket绑定到port端口
            serverChannel.socket().bind(localAddress);

            //获取一个boss线程
            Boss nextBoss = selectorRunnablePool.nextBoss();
            //向boss注册一个ServerSocket通道
            nextBoss.registerAcceptChannelTask(serverChannel);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

package com.zqw.nio.netty.n3;

import com.zqw.nio.netty.n3.pool.NioSelectorRunnablePool;

import java.net.InetSocketAddress;
import java.util.concurrent.Executors;


public class Start {

    public static void main(String[] args) {


        //初始化线程
        NioSelectorRunnablePool nioSelectorRunnablePool = new NioSelectorRunnablePool(Executors.newCachedThreadPool(), Executors.newCachedThreadPool());

        //获取服务类
        ServerBootstrap bootstrap = new ServerBootstrap(nioSelectorRunnablePool);

        //绑定端口
        bootstrap.bind(new InetSocketAddress(10101));

        System.out.println("start");
    }

}