public class ThreadCreateDemo1 {
    public static void main(String[] args) {
        MyThread thread = new MyThread();
        thread.start(); //该方法调用多次,出现IllegalThreadStateException
    }
}

class MyThread extends Thread {
    @Override
    public void run() {
        super.run();
        System.out.println("hellow_world!");
    }
}

public class ThreadCreateDemo2 {
    public static void main(String[] args) {
        Runnable runnable = new MyRunnable();
        Thread thread = new Thread(runnable);
        thread.start();
    }
}

class MyRunnable implements Runnable {
    public void run() {
        System.out.println("通过Runnable创建的线程!");
    }
}