Java接口的回调机制的实现

// 定义回调接口
interface Callback {
    void onEvent(String message);
}

// 调用方类
class EventSource {
    private Callback callback;

    // 注册回调接口
    public void registerCallback(Callback callback) {
        this.callback = callback;
    }

    // 模拟事件发生
    public void triggerEvent() {
        System.out.println("事件触发！");
        if (callback != null) {
            callback.onEvent("事件成功处理！");
        }
    }
}

// 调用者类
class EventListener implements Callback {
    @Override
    public void onEvent(String message) {
        System.out.println("Callback received: " + message);
    }
}

// 测试回调机制
public class CallBackDemo {
    public static void main(String[] args) {
        EventSource source = new EventSource(); // 调用方
        //EventListener listener = new EventListener(); // 调用者
        source.registerCallback(new EventListener());
        //source.registerCallback(listener); // 注册回调
        source.triggerEvent(); // 触发事件
    }
}

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class ButtonCallback {
    public static void main(String[] args) {
        JFrame frame = new JFrame("Callback Example");
        JButton button = new JButton("Click Me!");

        // 添加回调
        button.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                System.out.println("Button clicked!");
            }
        });

        frame.add(button);
        frame.setSize(200, 200);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

// 异步任务接口
interface TaskCallback {
    void onTaskComplete(String result);
}

// 异步任务实现类
class AsyncTask {
    private TaskCallback callback;

    public AsyncTask(TaskCallback callback) {
        this.callback = callback;
    }

    public void execute() {
        System.out.println("Task is running...");
        try {
            Thread.sleep(2000); // 模拟任务执行
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        callback.onTaskComplete("Task completed successfully!");
    }
}

// 测试异步任务
public class AsyncTaskDemo {
    public static void main(String[] args) {
        AsyncTask task = new AsyncTask(new TaskCallback() {
            @Override
            public void onTaskComplete(String result) {
                System.out.println("Callback received: " + result);
            }
        });

        task.execute();
    }
}

public class AsyncTaskDemo {
    public static void main(String[] args) {
        AsyncTask task = new AsyncTask(result -> {
            System.out.println("Callback received: " + result);
        });

        task.execute();
    }
}