聊天室消息轉發實現（待完成。。。。。）

1.服務器端代碼：

package net.qiujuer.lesson.sample.server;

import net.qiujuer.lesson.sample.server.handle.ClientHandler;
import net.qiujuer.library.clink.utils.CloseUtils;

import java.io.File;
import java.io.IOException;
import java.net.InetSocketAddress;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.ServerSocketChannel;
import java.nio.channels.SocketChannel;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class TCPServer implements ClientHandler.ClientHandlerCallback {
    private final int port;
    private final File cachePath;
    private final ExecutorService forwardingThreadPoolExecutor;
    private ClientListener listener;
    private List<ClientHandler> clientHandlerList = new ArrayList<>();
    private Selector selector;
    private ServerSocketChannel server;

    public TCPServer(int port, File cachePath) {
        this.port = port;
        this.cachePath = cachePath;
        // 轉發線程池
        this.forwardingThreadPoolExecutor = Executors.newSingleThreadExecutor();
    }

    public boolean start() {
        try {
            selector = Selector.open();
            ServerSocketChannel server = ServerSocketChannel.open();
            // 設置爲非阻塞
            server.configureBlocking(false);
            // 綁定本地端口
            server.socket().bind(new InetSocketAddress(port));
            // 註冊客戶端連接到達監聽
            server.register(selector, SelectionKey.OP_ACCEPT);

            this.server = server;


            System.out.println("服務器信息：" + server.getLocalAddress().toString());

            // 啓動客戶端監聽
            ClientListener listener = this.listener = new ClientListener();
            listener.start();
        } catch (IOException e) {
            e.printStackTrace();
            return false;
        }
        return true;
    }

    public void stop() {
        if (listener != null) {
            listener.exit();
        }

        CloseUtils.close(server);
        CloseUtils.close(selector);

        synchronized (TCPServer.this) {
            for (ClientHandler clientHandler : clientHandlerList) {
                clientHandler.exit();
            }

            clientHandlerList.clear();
        }

        // 停止線程池
        forwardingThreadPoolExecutor.shutdownNow();
    }

    public synchronized void broadcast(String str) {
        for (ClientHandler clientHandler : clientHandlerList) {
            clientHandler.send(str);
        }
    }

    @Override
    public synchronized void onSelfClosed(ClientHandler handler) {
        clientHandlerList.remove(handler);
    }

    @Override
    public void onNewMessageArrived(final ClientHandler handler, final String msg) {
        // 異步提交轉發任務
        forwardingThreadPoolExecutor.execute(() -> {
            synchronized (TCPServer.this) {
                for (ClientHandler clientHandler : clientHandlerList) {
                    if (clientHandler.equals(handler)) {
                        // 跳過自己
                        continue;
                    }
                    // 對其他客戶端發送消息
                    clientHandler.send(msg);
                }
            }
        });
    }

    private class ClientListener extends Thread {
        private boolean done = false;

        @Override
        public void run() {
            super.run();
            Selector selector = TCPServer.this.selector;
            System.out.println("服務器準備就緒～");
            // 等待客戶端連接
            do {
                // 得到客戶端
                try {
                    if (selector.select() == 0) {
                        if (done) {
                            break;
                        }
                        continue;
                    }

                    Iterator<SelectionKey> iterator = selector.selectedKeys().iterator();
                    while (iterator.hasNext()) {
                        if (done) {
                            break;
                        }

                        SelectionKey key = iterator.next();
                        iterator.remove();

                        // 檢查當前Key的狀態是否是我們關注的
                        // 客戶端到達狀態
                        if (key.isAcceptable()) {
                            ServerSocketChannel serverSocketChannel = (ServerSocketChannel) key.channel();
                            // 非阻塞狀態拿到客戶端連接
                            SocketChannel socketChannel = serverSocketChannel.accept();

                            try {
                                // 客戶端構建異步線程
                                ClientHandler clientHandler = new ClientHandler(socketChannel,
                                        TCPServer.this, cachePath);
                                // 添加同步處理
                                synchronized (TCPServer.this) {
                                    clientHandlerList.add(clientHandler);
                                }
                            } catch (IOException e) {
                                e.printStackTrace();
                                System.out.println("客戶端連接異常：" + e.getMessage());
                            }
                        }
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }

            } while (!done);

            System.out.println("服務器已關閉！");
        }

        void exit() {
            done = true;
            // 喚醒當前的阻塞
            selector.wakeup();
        }
    }
}

package net.qiujuer.lesson.sample.server.handle;


import net.qiujuer.lesson.sample.foo.Foo;
import net.qiujuer.library.clink.core.Connector;
import net.qiujuer.library.clink.core.Packet;
import net.qiujuer.library.clink.core.ReceivePacket;
import net.qiujuer.library.clink.utils.CloseUtils;

import java.io.File;
import java.io.IOException;
import java.nio.channels.SocketChannel;

public class ClientHandler extends Connector {
    private final File cachePath;
    private final ClientHandlerCallback clientHandlerCallback;
    private final String clientInfo;

    public ClientHandler(SocketChannel socketChannel, ClientHandlerCallback clientHandlerCallback, File cachePath) throws IOException {
        this.clientHandlerCallback = clientHandlerCallback;
        this.clientInfo = socketChannel.getRemoteAddress().toString();
        this.cachePath = cachePath;


        System.out.println("新客戶端連接：" + clientInfo);

        setup(socketChannel);
    }

    public void exit() {
        CloseUtils.close(this);
        System.out.println("客戶端已退出：" + clientInfo);
    }

    @Override
    public void onChannelClosed(SocketChannel channel) {
        super.onChannelClosed(channel);
        exitBySelf();
    }

    @Override
    protected File createNewReceiveFile() {
        return Foo.createRandomTemp(cachePath);
    }

    @Override
    protected void onReceivedPacket(ReceivePacket packet) {
        super.onReceivedPacket(packet);
        if (packet.type() == Packet.TYPE_MEMORY_STRING) {
            String string = (String) packet.entity();
            System.out.println(key.toString() + ":" + string);
            clientHandlerCallback.onNewMessageArrived(this, string);
        }
    }

    private void exitBySelf() {
        exit();
        clientHandlerCallback.onSelfClosed(this);
    }

    public interface ClientHandlerCallback {
        // 自身關閉通知
        void onSelfClosed(ClientHandler handler);

        // 收到消息時通知
        void onNewMessageArrived(ClientHandler handler, String msg);
    }
}

2.客戶端代碼：

package net.qiujuer.lesson.sample.client;


import net.qiujuer.lesson.sample.client.bean.ServerInfo;
import net.qiujuer.lesson.sample.foo.Foo;
import net.qiujuer.library.clink.box.FileSendPacket;
import net.qiujuer.library.clink.core.IoContext;
import net.qiujuer.library.clink.impl.IoSelectorProvider;

import java.io.*;

public class Client {
    public static void main(String[] args) throws IOException {
        File cachePath = Foo.getCacheDir("client");
        IoContext.setup()
                .ioProvider(new IoSelectorProvider())
                .start();

        ServerInfo info = UDPSearcher.searchServer(10000);
        System.out.println("Server:" + info);

        if (info != null) {
            TCPClient tcpClient = null;

            try {
                tcpClient = TCPClient.startWith(info, cachePath);
                if (tcpClient == null) {
                    return;
                }

                write(tcpClient);
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                if (tcpClient != null) {
                    tcpClient.exit();
                }
            }
        }


        IoContext.close();
    }


    private static void write(TCPClient tcpClient) throws IOException {
        // 構建鍵盤輸入流
        InputStream in = System.in;
        BufferedReader input = new BufferedReader(new InputStreamReader(in));

        do {
            // 鍵盤讀取一行
            String str = input.readLine();
            if ("00bye00".equalsIgnoreCase(str)) {
                break;
            }

            // --f url
            if (str.startsWith("--f")) {
                String[] array = str.split(" ");
                if (array.length >= 2) {
                    String filePath = array[1];
                    File file = new File(filePath);
                    if (file.exists() && file.isFile()) {
                        FileSendPacket packet = new FileSendPacket(file);
                        tcpClient.send(packet);
                        continue;
                    }
                }
            }

            // 發送字符串
            tcpClient.send(str);
        } while (true);
    }

}

package net.qiujuer.lesson.sample.client;


import net.qiujuer.lesson.sample.client.bean.ServerInfo;
import net.qiujuer.lesson.sample.foo.Foo;
import net.qiujuer.library.clink.core.Connector;
import net.qiujuer.library.clink.core.Packet;
import net.qiujuer.library.clink.core.ReceivePacket;
import net.qiujuer.library.clink.utils.CloseUtils;

import java.io.File;
import java.io.IOException;
import java.net.Inet4Address;
import java.net.InetSocketAddress;
import java.nio.channels.SocketChannel;

public class TCPClient extends Connector {
    private final File cachePath;

    public TCPClient(SocketChannel socketChannel, File cachePath) throws IOException {
        this.cachePath = cachePath;
        setup(socketChannel);
    }

    public void exit() {
        CloseUtils.close(this);
    }

    @Override
    public void onChannelClosed(SocketChannel channel) {
        super.onChannelClosed(channel);
        System.out.println("連接已關閉，無法讀取數據!");
    }

    @Override
    protected File createNewReceiveFile() {
        return Foo.createRandomTemp(cachePath);
    }

    @Override
    protected void onReceivedPacket(ReceivePacket packet) {
        super.onReceivedPacket(packet);
        if (packet.type() == Packet.TYPE_MEMORY_STRING) {
            String string = (String) packet.entity();
            System.out.println(key.toString() + ":" + string);
        }
    }

    public static TCPClient startWith(ServerInfo info, File cachePath) throws IOException {
        SocketChannel socketChannel = SocketChannel.open();

        // 連接本地，端口2000；超時時間3000ms
        socketChannel.connect(new InetSocketAddress(Inet4Address.getByName(info.getAddress()), info.getPort()));

        System.out.println("已發起服務器連接，並進入後續流程～");
        System.out.println("客戶端信息：" + socketChannel.getLocalAddress().toString());
        System.out.println("服務器信息：" + socketChannel.getRemoteAddress().toString());

        try {
            return new TCPClient(socketChannel, cachePath);
        } catch (Exception e) {
            System.out.println("連接異常");
            CloseUtils.close(socketChannel);
        }

        return null;
    }
}

最終演示效果如下：