/**
 * 
 * @author 閃電俠
 * @date 2018年10月14日
 * @Description:客戶端
 */
public class IOClient {

 public static void main(String[] args) {
  // TODO 創(chuàng)建多個線程，模擬多個客戶端連接服務端
  new Thread(() -> {
   try {
    Socket socket = new Socket("127.0.0.1", 3333);
    while (true) {
     try {
      socket.getOutputStream().write((new Date() + ": hello world").getBytes());
      Thread.sleep(2000);
     } catch (Exception e) {
     }
    }
   } catch (IOException e) {
   }
  }).start();

 }

}

/**
 * @author 閃電俠
 * @date 2018年10月14日
 * @Description: 服務端
 */
public class IOServer {

 public static void main(String[] args) throws IOException {
  // TODO 服務端處理客戶端連接請求
  ServerSocket serverSocket = new ServerSocket(3333);

  // 接收到客戶端連接請求之后為每個客戶端創(chuàng)建一個新的線程進行鏈路處理
  new Thread(() -> {
   while (true) {
    try {
     // 阻塞方法獲取新的連接
     Socket socket = serverSocket.accept();

     // 每一個新的連接都創(chuàng)建一個線程，負責讀取數據
     new Thread(() -> {
      try {
       int len;
       byte[] data = new byte[1024];
       InputStream inputStream = socket.getInputStream();
       // 按字節(jié)流方式讀取數據
       while ((len = inputStream.read(data)) != -1) {
        System.out.println(new String(data, 0, len));
       }
      } catch (IOException e) {
      }
     }).start();

    } catch (IOException e) {
    }

   }
  }).start();

 }

}

    // 1.根據操作系統(tǒng)選擇適當的底層 io復用方法
    ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
    serverSocketChannel.bind(new InetSocketAddress(8082));
    //2.設置為非阻塞
    serverSocketChannel.configureBlocking(false);
    //3.選擇與操作系統(tǒng)適配的選擇器
    Selector selector = Selector.open();
    //將 serverSocket 的OP_ACCEPT 事件注冊到 selector 選擇器上
    serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
    while (true) {
      // 4.監(jiān)聽當前連接建立情況
      int select = selector.select();
      if (select > 0) {
        //判斷連接業(yè)務類型
        Set<SelectionKey> set = selector.selectedKeys();
        Iterator<SelectionKey> iterator = set.iterator();
        while (iterator.hasNext()) {
          SelectionKey key = iterator.next();
          iterator.remove();
          //建立連接
          if (key.isAcceptable()) {
            ServerSocketChannel ssc = (ServerSocketChannel) key.channel();
            //通過 accept 方法獲取與 server端 已經創(chuàng)建好的 socket連接
            SocketChannel sc = ssc.accept();
            //設置為非阻塞
            sc.configureBlocking(false);
            //注冊感興趣的事件為 READ
            sc.register(selector, SelectionKey.OP_READ);
          }
          //可讀
          else if (key.isReadable()) {
            SocketChannel socket = (SocketChannel) key.channel();
            ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
            socket.read(byteBuffer);
            System.out.println(new String(byteBuffer.array(), StandardCharsets.UTF_8));
            key.interestOps(SelectionKey.OP_WRITE);
          }
          //可寫
          else if (key.isWritable()) {
            SocketChannel socket = (SocketChannel) key.channel();
            socket.write(ByteBuffer.wrap("I'm receive your message".getBytes(StandardCharsets.UTF_8)));
            socket.close();
            System.out.println("連接關閉成功！");
          }
        }
      }
    }

  private static void server() throws IOException {
    //根據操作系統(tǒng)建立對應的底層操作類
    AsynchronousServerSocketChannel channel = AsynchronousServerSocketChannel.open();
    channel.bind(new InetSocketAddress(8082));
    while (true) {
      Future<AsynchronousSocketChannel> future = channel.accept();
      try {
        AsynchronousSocketChannel asc = future.get();
        System.out.println("建立連接成功");
        Future<Integer> write = asc.write(ByteBuffer.wrap("Now let's exchange datas".getBytes(StandardCharsets.UTF_8)));
        while (!write.isDone()) {
          TimeUnit.SECONDS.sleep(2);
        }
        System.out.println("發(fā)送數據完成");
        asc.close();
      } catch (Exception e) {
        e.printStackTrace();
      }
    }
  }

  private static void client() throws Exception {
    AsynchronousSocketChannel socketChannel = AsynchronousSocketChannel.open();
    Future<Void> future = socketChannel.connect(new InetSocketAddress(8082));
    while (!future.isDone()) {
      TimeUnit.SECONDS.sleep(2);
    }
    ByteBuffer buffer = ByteBuffer.allocate(1024);
    Future<Integer> read = socketChannel.read(buffer);
    while (!read.isDone()) {
      TimeUnit.SECONDS.sleep(2);
    }
    System.out.println("接收服務器數據:" + new String(buffer.array(), 0, read.get()));
  }