创建线程的三种方式

1. 继承Thread类，重写run方法

public class MyThread extends Thread {
    public void run() {
        System.out.println("Hello from MyThread!");
    }
}

public class Main {
    public static void main(String[] args) {
        MyThread thread = new MyThread();
        thread.start();
    }
}

// 输出结果
Hello from MyThread!

2. 实现Runnable接口，实现run方法

public class MyRunnable implements Runnable {
    public void run() {
        System.out.println("Hello from MyRunnable!");
    }
}

public class Main {
    public static void main(String[] args) {
        Thread thread = new Thread(new MyRunnable());
        thread.start();
    }
}

// 输出结果
Hello from MyRunnable!

2. 使用Callable和Future创建有返回值的线程

import java.util.concurrent.Callable;
import java.util.concurrent.Future;
import java.util.concurrent.FutureTask;

public class MyCallable implements Callable<String> {
    public String call() {
        return "Hello from MyCallable!";
    }
}

public class Main {
    public static void main(String[] args) throws Exception {
        Callable<String> callable = new MyCallable();
        FutureTask<String> futureTask = new FutureTask<>(callable);
        Thread thread = new Thread(futureTask);
        thread.start();
        String result = futureTask.get();
        System.out.println(result);
    }
}

// 输出结果
Hello from MyCallable!

​ 以上是Java创建线程的三种方式，分别使用了

• 继承Thread类、
• 实现Runnable接口、
• 使用Callable和Future创建有返回值的线程。

通过这三种方式，我们可以灵活地创建多线程应用程序。