/**
 * A thread can be in only one state at a given point in time.
 * These states are virtual machine states which do not reflect
 * any operating system thread states.
 * 一个线程在特定的时刻，只能有一个状态。
 * 这些状态是虚拟机的状态，不能反映任何操作系统的线程状态
 * @since   1.5
 */
public enum State {
    /**
     * Thread state for a thread which has not yet started.
     * 线程未开始的状态
     */
    NEW,
    /**
     * Thread state for a runnable thread.  A thread in the runnable
     * state is executing in the Java virtual machine but it may
     * be waiting for other resources from the operating system
     * such as processor.
     * 可运行的线程状态，此状态的线程正在JVM中运行，
     * 但也有可能在等待操作系统的其他资源，例如处理器
     */
    RUNNABLE,
    /**
     * Thread state for a thread blocked waiting for a monitor lock.
     * A thread in the blocked state is waiting for a monitor lock
     * to enter a synchronized block/method or
     * reenter a synchronized block/method after calling
     * 阻塞状态的线程在等待一个监视器锁去进入同步代码块/方法，
     * 或者调用后重新进入同步代码块/方法
     */
    BLOCKED,
    /**
     * Thread state for a waiting thread.
     * A thread is in the waiting state due to calling one of the following methods:
     * Object.wait()
     * Thread.join()
     * LockSupport.park()
     * A thread in the waiting state is waiting for another thread to
     * perform a particular action.
     * 由于调用了Object.wait()、Thread.join()、LockSupport.park()其中一个方法，线程进入等待状态
     * 处于等待状态的线程，正在在等待另一个线程执行特定的操作
     */
    WAITING,
    /**
     * Thread state for a waiting thread with a specified waiting time.
     * A thread is in the timed waiting state due to calling one of
     * the following methods with a specified positive waiting time:
     * Thread.sleep()
     * Object.wait()
     * LockSupport.parkNanos()
     * LockSupport.parkUntil()
     * 有指定等待时间的线程等待状态
     * 由于调用了Thread.sleep(long)、Object.wait(long)、Thread.join(long)、
     * LockSupport.parkNanos(long)、LockSupport.parkUntil(long)其中一个方法并传入了正（数）时间参数，
     * 线程处于有时间限制的等待状态
     */
    TIMED_WAITING,
    /**
     * Thread state for a terminated thread.
     * The thread has completed execution.
     * 线程已经执行完成，处于终止状态
     */
    TERMINATED;
}

public static void main(String[] args) throws Exception {
    Thread thread = new Thread(new Runnable() {
        @Override
        public void run() {
            System.out.println("执行run()，thread线程状态：" + Thread.currentThread().getState().toString());
            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("sleep结束，thread线程状态：" + Thread.currentThread().getState().toString());
        }
    });
    System.out.println("未调用start()，thread线程状态：" + thread.getState().toString());
    thread.start();
    // 睡眠200毫秒，让thread被调度起来，进入sleep
    Thread.sleep(200);
    System.out.println("线程sleep，thread线程状态：" + thread.getState().toString());
    // 睡眠2秒，让thread执行完成
    Thread.sleep(2000);
    System.out.println("线程执行完成，thread线程状态：" + thread.getState().toString());
}