java，辨别子线程、主线程

public class Main {

    public static void main(String[] args) throws Exception {
        Thread t = new Thread(new Worker());//Thread-0
        t.start();//Thread-0

        //Thread.sleep(200);//main线程,与Thread.currentThread().sleep(200);同义
        System.out.println("Thread.sleep(200)");
        Thread.currentThread().sleep(200);//main线程
        t.interrupt();//Thread-0

        System.out.println("t.getName():" + t.getName());//Thread-0
        System.out.println("2 Thread.currentThread().getName():" + Thread.currentThread().getName());//main线程

        System.out.println("Main thread stopped.");
    }

    public static class Worker implements Runnable {
        public void run() {
            System.out.println("Worker started.");
            try {
                System.out.println("1 Thread.currentThread().getName():" + Thread.currentThread().getName());//Thread-0
                Thread.sleep(500);//Thread-0
            } catch (InterruptedException e) {
                Thread curr = Thread.currentThread();//Thread-0
                System.out.println("curr.getName():" + curr.getName());//Thread-0
            }
            System.out.println("Worker stopped.");
        }
    }

}

输出：

Thread.sleep(200)
Worker started.
1 Thread.currentThread().getName():Thread-0
t.getName():Thread-0
curr.getName():Thread-0
2 Thread.currentThread().getName():main
Worker stopped.
Main thread stopped.

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main（）中的Thread是主线程，

从Runnable实现的线程、从Thread继承的线程是子线程，

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Worker started.不是最先输出的，因为线程start是就绪状态，run是运行状态，start会异步调用run方法，

参考：https://blog.csdn.net/Alex___Zhao/article/details/75137390  漫谈操作系统9 -- 线程运行状态

https://blog.csdn.net/tornado886/article/details/4524346  Thread的run（）与start（）的区别