public static void main(String[] args) {
    try {
        // 監(jiān)聽端口
        ServerSocket serverSocket = new ServerSocket(8080);
        // 等待客戶端的連接過來,如果沒有連接過來，就會(huì)阻塞
        while (true) {
            // 阻塞IO中一個(gè)線程只能處理一個(gè)連接
            Socket socket = serverSocket.accept();
            System.out.println("客戶端建立連接:"+socket.getPort());
            String line = null;
            try {
                BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
                line = bufferedReader.readLine();
                System.out.println("客戶端的數(shù)據(jù)：" + line);
                BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
                bufferedWriter.write("ok\n");
                bufferedWriter.flush();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
}

public static List<SocketChannel> channelList = new ArrayList<>();
public static void main(String[] args) {
    try {
        // 相當(dāng)于serverSocket
        // 1.支持非阻塞  2.數(shù)據(jù)總是寫入buffer,讀取也是從buffer中去讀  3.可以同時(shí)讀寫
        ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
        // 設(shè)置非阻塞
        serverSocketChannel.configureBlocking(false);
        serverSocketChannel.socket().bind(new InetSocketAddress(8080));
        while (true){
            // 這里將不再阻塞
            SocketChannel socketChannel = serverSocketChannel.accept();
            if(socketChannel != null){
                socketChannel.configureBlocking(false);
                channelList.add(socketChannel);
            }else {
                System.out.println("沒有請(qǐng)求過來?。?！");
            }
            for (SocketChannel client : channelList){
                ByteBuffer byteBuffer = ByteBuffer.allocate(1024);
                // 也不阻塞
                int num = client.read(byteBuffer);
                if(num>0){
                    System.out.println("客戶端端口："+ client.socket().getPort()+",客戶端收據(jù)："+new String(byteBuffer.array()));
                }else {
                    System.out.println("等待客戶端寫數(shù)據(jù)");
                }
            }
        }
    } catch (IOException e) {
        e.printStackTrace();
    }
}

public class NewIOServer {
    static Selector selector;
    public static void main(String[] args) {
        try {
            selector = Selector.open();
            ServerSocketChannel serverSocketChannel = ServerSocketChannel.open();
            serverSocketChannel.configureBlocking(false);
            serverSocketChannel.socket().bind(new InetSocketAddress(8080));
            // 需要把serverSocketChannel注冊到多路復(fù)用器上
            serverSocketChannel.register(selector, SelectionKey.OP_ACCEPT);
            while (true) {
                // 阻塞
                selector.select();
                Set<SelectionKey> selectionKeys = selector.selectedKeys();
                Iterator<SelectionKey> iterator = selectionKeys.iterator();
                while (iterator.hasNext()) {
                    SelectionKey key = iterator.next();
                    iterator.remove();
                    if (key.isAcceptable()) {
                        handlerAccept(key);
                    } else if (key.isReadable()) {
                        handlerRead(key);
                    }else if(key.isWritable()){
                    }
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    private static void handlerRead(SelectionKey key) {
        SocketChannel socketChannel = (SocketChannel) key.channel();
        ByteBuffer allocate = ByteBuffer.allocate(1024);
        try {
            socketChannel.read(allocate);
            System.out.println("server msg:" + new String(allocate.array()));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    private static void handlerAccept(SelectionKey key) {
        ServerSocketChannel serverSocketChannel = (ServerSocketChannel) key.channel();
        // 不阻塞
        try {
            SocketChannel socketChannel = serverSocketChannel.accept();
            socketChannel.configureBlocking(false);
            socketChannel.write(ByteBuffer.wrap("It‘s server msg".getBytes()));
            // 讀取客戶端的數(shù)據(jù)
            socketChannel.register(selector, SelectionKey.OP_READ);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

public class NewIOClient {
    static Selector selector;
    public static void main(String[] args) {
        try {
            selector = Selector.open();
            SocketChannel socketChannel = SocketChannel.open();
            socketChannel.configureBlocking(false);
            socketChannel.connect(new InetSocketAddress("localhost", 8080));
            // 需要把socketChannel注冊到多路復(fù)用器上
            socketChannel.register(selector, SelectionKey.OP_CONNECT);
            while (true) {
                // 阻塞
                selector.select();
                Set<SelectionKey> selectionKeys = selector.selectedKeys();
                Iterator<SelectionKey> iterator = selectionKeys.iterator();
                while (iterator.hasNext()) {
                    SelectionKey key = iterator.next();
                    iterator.remove();
                    if (key.isConnectable()) {
                        handlerConnect(key);
                    } else if (key.isReadable()) {
                        handlerRead(key);
                    } else if (key.isWritable()) {
                    }
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    private static void handlerRead(SelectionKey key) {
        SocketChannel socketChannel = (SocketChannel) key.channel();
        ByteBuffer allocate = ByteBuffer.allocate(1024);
        try {
            socketChannel.read(allocate);
            System.out.println("client msg:" + new String(allocate.array()));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    private static void handlerConnect(SelectionKey key) throws IOException {
        SocketChannel socketChannel = (SocketChannel) key.channel();
        if (socketChannel.isConnectionPending()) {
            socketChannel.finishConnect();
        }
        socketChannel.configureBlocking(false);
        socketChannel.write(ByteBuffer.wrap("it‘s client msg".getBytes()));
        socketChannel.register(selector,SelectionKey.OP_READ);
    }
}

public class AIOServer {
    public static void main(String[] args) throws Exception {
        // 創(chuàng)建一個(gè)SocketChannel并綁定了8080端口
        final AsynchronousServerSocketChannel serverChannel =
                AsynchronousServerSocketChannel.open().bind(new InetSocketAddress(8080));
        serverChannel.accept(null, new CompletionHandler<AsynchronousSocketChannel, Object>() {
            @Override
            public void completed(AsynchronousSocketChannel socketChannel, Object attachment) {
                try {
                    // 打印線程的名字
                    System.out.println("2--"+Thread.currentThread().getName());
                    System.out.println(socketChannel.getRemoteAddress());
                    ByteBuffer buffer = ByteBuffer.allocate(1024);
                    // socketChannel異步的讀取數(shù)據(jù)到buffer中
                    socketChannel.read(buffer, buffer, new CompletionHandler<Integer, ByteBuffer>() {
                        @Override
                        public void completed(Integer result, ByteBuffer buffer) {
                            // 打印線程的名字
                            System.out.println("3--"+Thread.currentThread().getName());
                            buffer.flip();
                            System.out.println(new String(buffer.array(), 0, result));
                            socketChannel.write(ByteBuffer.wrap("HelloClient".getBytes()));
                        }
                        @Override
                        public void failed(Throwable exc, ByteBuffer buffer) {
                            exc.printStackTrace();
                        }
                    });
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            @Override
            public void failed(Throwable exc, Object attachment) {
                exc.printStackTrace();
            }
        });
        System.out.println("1--"+Thread.currentThread().getName());
        Thread.sleep(Integer.MAX_VALUE);
    }
}

public class AIOClient {
    private final AsynchronousSocketChannel client;
    public AIOClient() throws IOException {
        client = AsynchronousSocketChannel.open();
    }
    public static void main(String[] args) throws Exception {
        new AIOClient().connect("localhost",8080);
    }
    public void connect(String host, int port) throws Exception {
        // 客戶端向服務(wù)端發(fā)起連接
        client.connect(new InetSocketAddress(host, port), null, new CompletionHandler<Void, Object>() {
            @Override
            public void completed(Void result, Object attachment) {
                try {
                    client.write(ByteBuffer.wrap("這是一條測試數(shù)據(jù)".getBytes())).get();
                    System.out.println("已發(fā)送到服務(wù)端");
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
            @Override
            public void failed(Throwable exc, Object attachment) {
                exc.printStackTrace();
            }
        });
        final ByteBuffer bb = ByteBuffer.allocate(1024);
        // 客戶端接收服務(wù)端的數(shù)據(jù)，獲取的數(shù)據(jù)寫入到bb中
        client.read(bb, null, new CompletionHandler<Integer, Object>() {
            @Override
            public void completed(Integer result, Object attachment) {
                // 服務(wù)端返回?cái)?shù)據(jù)的長度result
                System.out.println("I/O操作完成：" + result);
                System.out.println("獲取反饋結(jié)果：" + new String(bb.array()));
            }
            @Override
            public void failed(Throwable exc, Object attachment) {
                exc.printStackTrace();
            }
        });
        try {
            Thread.sleep(Integer.MAX_VALUE);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}