详解Java的线程状态

private volatile int threadStatus = 0;

public enum State {
    NEW,			//	新建状态
    RUNNABLE,		//	执行状态
    BLOCKED,		//	阻塞状态
    WaiTING,		//	无限期等待状态
    TIMED_WAITING,  //  有限期等待状态
    TERMINATED;     //  退出状态
}

State state = thread.getState();

Thread t = new Thread(() -> {
    System.out.println("sleep");
    //	休眠2秒
    ThreadUtil.sleep(2000);
    System.out.println("run");
});

//	启动前先打印一下线程状态
System.out.println(t.getState());
//	启动线程
t.start();
//	启动后立即打印一次线程状态
System.out.println(t.getState());

//	每隔500毫秒打印一次线程状态
while (true) {
    ThreadUtil.sleep(500);
    System.out.println(t.getState());
}

private static Object lock = new Object();

public static void main(String[] args) {
    Runnable runnable = () -> {
        //	加锁
        synchronized (lock) {
            System.out.println(Thread.currentThread().getName() + " lock");
            ThreadUtil.sleep(2000);
        }
        System.out.println(Thread.currentThread().getName() + " exit");
    };

    Thread t1 = new Thread(runnable, "t1");
    Thread t2 = new Thread(runnable, "t2");

    t1.start();
    t2.start();

    while (true) {
        ThreadUtil.sleep(500);
        System.out.println(t1.getName() + ":" + t1.getState());
        System.out.println(t2.getName() + ":" + t2.getState());
    }
}

private static Object obj = new Object();

public static void main(String[] args) {
    Runnable runnable = () -> {
        synchronized (obj) {
            try {
                //	等待
                obj.wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            System.out.println("exit");
        }
    };

    Thread t1 = new Thread(runnable, "t1");
    System.out.println(t1.getName() + ":" + t1.getState());
    t1.start();
    System.out.println(t1.getName() + ":" + t1.getState());

    for (int i = 0; i < 20; i++) {
        ThreadUtil.sleep(500);
        if(i == 3) {
            synchronized (obj) {
                //	唤醒
                obj.notify();
            }
        }
        System.out.println(t1.getName() + ":" + t1.getState());
    }
}