// 示例代碼
import java.nio.Buffer;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardOpenOption;
public class NIOExample {
    public static void main(String[] args) {
        try {
            // 打開文件通道
            Path path = Paths.get("example.txt");
            FileChannel channel = FileChannel.open(path, StandardOpenOption.READ);
            // 創(chuàng)建緩沖區(qū)
            ByteBuffer buffer = ByteBuffer.allocate(1024);
            // 從通道讀取數(shù)據(jù)到緩沖區(qū)
            int bytesRead = channel.read(buffer);
            // 重置緩沖區(qū)的位置和限制
            buffer.flip();
            // 從緩沖區(qū)讀取數(shù)據(jù)
            while (buffer.hasRemaining()) {
                System.out.print((char) buffer.get());
            }
            // 關(guān)閉通道
            channel.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

// 創(chuàng)建直接緩沖區(qū)
ByteBuffer buffer = ByteBuffer.allocateDirect(1024);

// 創(chuàng)建堆緩沖區(qū)
ByteBuffer buffer = ByteBuffer.allocate(1024);

// 打開文件通道
Path path = Paths.get("example.txt");
FileChannel channel = FileChannel.open(path, StandardOpenOption.READ);
// 創(chuàng)建緩沖區(qū)
ByteBuffer buffer = ByteBuffer.allocate(1024);
// 從通道讀取數(shù)據(jù)到緩沖區(qū)
int bytesRead = channel.read(buffer);
// 重置緩沖區(qū)的位置和限制
buffer.flip();
// 從緩沖區(qū)讀取數(shù)據(jù)
while (buffer.hasRemaining()) {
    System.out.print((char) buffer.get());
}
// 關(guān)閉通道
channel.close();

// 打開SocketChannel
SocketChannel socketChannel = SocketChannel.open();
socketChannel.connect(new InetSocketAddress("example.com", 8080));
// 創(chuàng)建緩沖區(qū)
ByteBuffer buffer = ByteBuffer.allocate(1024);
// 從SocketChannel讀取數(shù)據(jù)到緩沖區(qū)
int bytesRead = socketChannel.read(buffer);
// 重置緩沖區(qū)的位置和限制
buffer.flip();
// 從緩沖區(qū)讀取數(shù)據(jù)
while (buffer.hasRemaining()) {
    System.out.print((char) buffer.get());
}
// 關(guān)閉SocketChannel
socketChannel.close();

// 打開選擇器
Selector selector = Selector.open();
// 將通道注冊到選擇器上
channel.register(selector, SelectionKey.OP_READ);
// 循環(huán)處理選擇器上的事件
while (true) {
    // 選擇器等待事件
    int readyChannels = selector.select();
    // 處理選擇器上的事件
    if (readyChannels > 0) {
        Set<SelectionKey> selectedKeys = selector.selectedKeys();
        for (SelectionKey key : selectedKeys) {
            if (key.isReadable()) {
                // 處理讀事件
            } else if (key.isWritable()) {
                // 處理寫事件
            }
        }
        selectedKeys.clear();
    }
}
// 關(guān)閉選擇器
selector.close();

// 打開SocketChannel并設(shè)置為非阻塞模式
SocketChannel socketChannel = SocketChannel.open();
socketChannel.configureBlocking(false);
// 連接服務(wù)器
socketChannel.connect(new InetSocketAddress("example.com", 8080));
// 循環(huán)等待連接完成
while (!socketChannel.finishConnect()) {
    // 連接未完成，繼續(xù)執(zhí)行其他任務(wù)
}
// 連接完成后進(jìn)行數(shù)據(jù)讀寫操作
if (socketChannel.isConnected()) {
    ByteBuffer buffer = ByteBuffer.allocate(1024);
    // 從SocketChannel讀取數(shù)據(jù)
    int bytesRead = socketChannel.read(buffer);
    // 從緩沖區(qū)讀取數(shù)據(jù)
    buffer.flip();
    while (buffer.hasRemaining()) {
        System.out.print((char) buffer.get());
    }
    // 寫入數(shù)據(jù)到SocketChannel
    String message = "Hello, Server!";
    buffer.clear();
    buffer.put(message.getBytes());
    buffer.flip();
    while (buffer.hasRemaining()) {
        socketChannel.write(buffer);
    }
    // 關(guān)閉SocketChannel
    socketChannel.close();
}

// 創(chuàng)建事件監(jiān)聽器接口
interface EventListener {
    void onEvent(Event event);
}
// 創(chuàng)建事件處理器類
class EventHandler implements EventListener {
    @Override
    public void onEvent(Event event) {
        // 處理事件的邏輯
        System.out.println("處理事件：" + event);
    }
}
// 創(chuàng)建事件類
class Event {
    private String name;
    public Event(String name) {
        this.name = name;
    }
    @Override
    public String toString() {
        return "Event{" +
                "name='" + name + '\'' +
                '}';
    }
}
// 創(chuàng)建事件源類
class EventSource {
    private EventListener listener;
    public void setEventListener(EventListener listener) {
        this.listener = listener;
    }
    public void fireEvent(Event event) {
        // 觸發(fā)事件
        if (listener != null) {
            listener.onEvent(event);
        }
    }
}
// 使用事件監(jiān)聽器和處理器
public class Main {
    public static void main(String[] args) {
        // 創(chuàng)建事件處理器
        EventHandler eventHandler = new EventHandler();
        // 創(chuàng)建事件源
        EventSource eventSource = new EventSource();
        eventSource.setEventListener(eventHandler);
        // 創(chuàng)建事件
        Event event = new Event("點擊事件");
        // 觸發(fā)事件
        eventSource.fireEvent(event);
    }
}