public static void main(String[] args) {        Thread t = new Thread(new InnerRunnable());        t.start();        System.out.println("        thread: " + t);        long threadId = t.getId();                // 一：通过线程组遍历获得线程        Thread s = findThread(threadId);        System.out.println("   find thread: " + s);        System.out.println("current thread: " + Thread.currentThread());                               // 二：通过 JMX 可以通过线程 ID 获得线程信息        ThreadMXBean tmx = ManagementFactory.getThreadMXBean();        ThreadInfo info = tmx.getThreadInfo(threadId);        System.out.println(info.getThreadState());                        s.interrupt();    }    /**     * 通过线程组获得线程     *     * @param threadId     * @return     */    public static Thread findThread(long threadId) {        ThreadGroup group = Thread.currentThread().getThreadGroup();        while(group != null) {            Thread[] threads = new Thread[(int)(group.activeCount() * 1.2)];            int count = group.enumerate(threads, true);            for(int i = 0; i < count; i++) {                if(threadId == threads[i].getId()) {                    return threads[i];                }            }            group = group.getParent();        }        return null;    }    private static class InnerRunnable implements Runnable {        private int i = 0;        public void run() {            try {                while (!Thread.currentThread().isInterrupted()) {                    System.out.println(i++);                    Thread.sleep(10);                }            } catch (InterruptedException e) {                System.out.println("mythread is interrupted!");            }        }    }